diff --git a/src/Bundle/ChillMainBundle/Controller/UserGroupApiController.php b/src/Bundle/ChillMainBundle/Controller/UserGroupApiController.php
new file mode 100644
index 000000000..602b84ec5
--- /dev/null
+++ b/src/Bundle/ChillMainBundle/Controller/UserGroupApiController.php
@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\MainBundle\Controller;
+
+use Chill\MainBundle\CRUD\Controller\ApiController;
+
+class UserGroupApiController extends ApiController {}
diff --git a/src/Bundle/ChillMainBundle/DataFixtures/ORM/LoadUserGroup.php b/src/Bundle/ChillMainBundle/DataFixtures/ORM/LoadUserGroup.php
new file mode 100644
index 000000000..614a83515
--- /dev/null
+++ b/src/Bundle/ChillMainBundle/DataFixtures/ORM/LoadUserGroup.php
@@ -0,0 +1,68 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\MainBundle\DataFixtures\ORM;
+
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
+use Doctrine\Bundle\FixturesBundle\Fixture;
+use Doctrine\Bundle\FixturesBundle\FixtureGroupInterface;
+use Doctrine\Persistence\ObjectManager;
+
+class LoadUserGroup extends Fixture implements FixtureGroupInterface
+{
+    public static function getGroups(): array
+    {
+        return ['user-group'];
+    }
+
+    public function load(ObjectManager $manager)
+    {
+        $centerASocial = $manager->getRepository(User::class)->findOneBy(['username' => 'center a_social']);
+        $centerBSocial = $manager->getRepository(User::class)->findOneBy(['username' => 'center b_social']);
+        $multiCenter = $manager->getRepository(User::class)->findOneBy(['username' => 'multi_center']);
+        $administrativeA = $manager->getRepository(User::class)->findOneBy(['username' => 'center a_administrative']);
+        $administrativeB = $manager->getRepository(User::class)->findOneBy(['username' => 'center b_administrative']);
+
+        $level1 = $this->generateLevelGroup('Niveau 1', '#eec84aff', '#000000ff', 'level');
+        $level1->addUser($centerASocial)->addUser($centerBSocial);
+        $manager->persist($level1);
+
+        $level2 = $this->generateLevelGroup('Niveau 2', ' #e2793dff', '#000000ff', 'level');
+        $level2->addUser($multiCenter);
+        $manager->persist($level2);
+
+        $level3 = $this->generateLevelGroup('Niveau 3', ' #df4949ff', '#000000ff', 'level');
+        $level3->addUser($multiCenter);
+        $manager->persist($level3);
+
+        $tss = $this->generateLevelGroup('Travailleur sociaux', '#43b29dff', '#000000ff', '');
+        $tss->addUser($multiCenter)->addUser($centerASocial)->addUser($centerBSocial);
+        $manager->persist($tss);
+        $admins = $this->generateLevelGroup('Administratif', '#334d5cff', '#000000ff', '');
+        $admins->addUser($administrativeA)->addUser($administrativeB);
+        $manager->persist($admins);
+
+        $manager->flush();
+    }
+
+    private function generateLevelGroup(string $title, string $backgroundColor, string $foregroundColor, string $excludeKey): UserGroup
+    {
+        $userGroup = new UserGroup();
+
+        return $userGroup
+            ->setLabel(['fr' => $title])
+            ->setBackgroundColor($backgroundColor)
+            ->setForegroundColor($foregroundColor)
+            ->setExcludeKey($excludeKey)
+        ;
+    }
+}
diff --git a/src/Bundle/ChillMainBundle/DependencyInjection/ChillMainExtension.php b/src/Bundle/ChillMainBundle/DependencyInjection/ChillMainExtension.php
index 4dde2076c..3170cadee 100644
--- a/src/Bundle/ChillMainBundle/DependencyInjection/ChillMainExtension.php
+++ b/src/Bundle/ChillMainBundle/DependencyInjection/ChillMainExtension.php
@@ -24,6 +24,7 @@ use Chill\MainBundle\Controller\LocationTypeController;
 use Chill\MainBundle\Controller\NewsItemController;
 use Chill\MainBundle\Controller\RegroupmentController;
 use Chill\MainBundle\Controller\UserController;
+use Chill\MainBundle\Controller\UserGroupApiController;
 use Chill\MainBundle\Controller\UserJobApiController;
 use Chill\MainBundle\Controller\UserJobController;
 use Chill\MainBundle\DependencyInjection\Widget\Factory\WidgetFactoryInterface;
@@ -59,6 +60,7 @@ use Chill\MainBundle\Entity\LocationType;
 use Chill\MainBundle\Entity\NewsItem;
 use Chill\MainBundle\Entity\Regroupment;
 use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
 use Chill\MainBundle\Entity\UserJob;
 use Chill\MainBundle\Form\CenterType;
 use Chill\MainBundle\Form\CivilityType;
@@ -803,6 +805,21 @@ class ChillMainExtension extends Extension implements
                         ],
                     ],
                 ],
+                [
+                    'class' => UserGroup::class,
+                    'controller' => UserGroupApiController::class,
+                    'name' => 'user-group',
+                    'base_path' => '/api/1.0/main/user-group',
+                    'base_role' => 'ROLE_USER',
+                    'actions' => [
+                        '_index' => [
+                            'methods' => [
+                                Request::METHOD_GET => true,
+                                Request::METHOD_HEAD => true,
+                            ],
+                        ],
+                    ],
+                ],
             ],
         ]);
     }
diff --git a/src/Bundle/ChillMainBundle/Entity/UserGroup.php b/src/Bundle/ChillMainBundle/Entity/UserGroup.php
index 3bd9870a6..470a21a70 100644
--- a/src/Bundle/ChillMainBundle/Entity/UserGroup.php
+++ b/src/Bundle/ChillMainBundle/Entity/UserGroup.php
@@ -14,17 +14,21 @@ namespace Chill\MainBundle\Entity;
 use Doctrine\Common\Collections\ArrayCollection;
 use Doctrine\Common\Collections\Collection;
 use Doctrine\ORM\Mapping as ORM;
+use Symfony\Component\Serializer\Annotation as Serializer;
 
 #[ORM\Entity]
 #[ORM\Table(name: 'chill_main_user_group')]
+#[Serializer\DiscriminatorMap(typeProperty: 'type', mapping: ['user_group' => UserGroup::class])]
 class UserGroup
 {
     #[ORM\Id]
     #[ORM\GeneratedValue]
     #[ORM\Column(type: \Doctrine\DBAL\Types\Types::INTEGER, nullable: false)]
+    #[Serializer\Groups(['read'])]
     private ?int $id = null;
 
     #[ORM\Column(type: \Doctrine\DBAL\Types\Types::JSON, nullable: false, options: ['default' => '[]'])]
+    #[Serializer\Groups(['read'])]
     private array $label = [];
 
     /**
@@ -34,6 +38,24 @@ class UserGroup
     #[ORM\JoinTable(name: 'chill_main_user_group_user')]
     private Collection $users;
 
+    #[ORM\Column(type: 'text', nullable: false, options: ['default' => '#ffffffff'])]
+    #[Serializer\Groups(['read'])]
+    private string $backgroundColor = '#ffffffff';
+
+    #[ORM\Column(type: 'text', nullable: false, options: ['default' => '#000000ff'])]
+    #[Serializer\Groups(['read'])]
+    private string $foregroundColor = '#000000ff';
+
+    /**
+     * Groups with same exclude key are mutually exclusive: adding one in a many-to-one relationship
+     * will exclude others.
+     *
+     * An empty string means "no exclusion"
+     */
+    #[ORM\Column(type: 'text', nullable: false, options: ['default' => ''])]
+    #[Serializer\Groups(['read'])]
+    private string $excludeKey = '';
+
     public function __construct()
     {
         $this->users = new ArrayCollection();
@@ -71,4 +93,47 @@ class UserGroup
     {
         return $this->users;
     }
+
+    public function getForegroundColor(): string
+    {
+        return $this->foregroundColor;
+    }
+
+    public function getExcludeKey(): string
+    {
+        return $this->excludeKey;
+    }
+
+    public function getBackgroundColor(): string
+    {
+        return $this->backgroundColor;
+    }
+
+    public function setForegroundColor(string $foregroundColor): self
+    {
+        $this->foregroundColor = $foregroundColor;
+
+        return $this;
+    }
+
+    public function setBackgroundColor(string $backgroundColor): self
+    {
+        $this->backgroundColor = $backgroundColor;
+
+        return $this;
+    }
+
+    public function setExcludeKey(string $excludeKey): self
+    {
+        $this->excludeKey = $excludeKey;
+
+        return $this;
+    }
+
+    public function setLabel(array $label): self
+    {
+        $this->label = $label;
+
+        return $this;
+    }
 }
diff --git a/src/Bundle/ChillMainBundle/Resources/public/types.ts b/src/Bundle/ChillMainBundle/Resources/public/types.ts
index 2e33b8248..ada3089a0 100644
--- a/src/Bundle/ChillMainBundle/Resources/public/types.ts
+++ b/src/Bundle/ChillMainBundle/Resources/public/types.ts
@@ -42,6 +42,17 @@ export interface User {
   // todo: mainCenter; mainJob; etc..
 }
 
+export interface UserGroup {
+    type: "chill_main_user_group",
+    id: number,
+    label: TranslatableString,
+    backgroundColor: string,
+    foregroundColor: string,
+    excludeKey: string,
+}
+
+export type UserGroupOrUser = User | UserGroup;
+
 export interface UserAssociatedInterface {
   type: "user";
   id: number;
diff --git a/src/Bundle/ChillMainBundle/Tests/Validation/Validator/UserGroupDoNotExcludeTest.php b/src/Bundle/ChillMainBundle/Tests/Validation/Validator/UserGroupDoNotExcludeTest.php
new file mode 100644
index 000000000..d6d1c9887
--- /dev/null
+++ b/src/Bundle/ChillMainBundle/Tests/Validation/Validator/UserGroupDoNotExcludeTest.php
@@ -0,0 +1,91 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\MainBundle\Tests\Validation\Validator;
+
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
+use Chill\MainBundle\Templating\TranslatableStringHelperInterface;
+use Chill\MainBundle\Validation\Validator\UserGroupDoNotExclude;
+use Symfony\Component\Validator\Test\ConstraintValidatorTestCase;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+class UserGroupDoNotExcludeTest extends ConstraintValidatorTestCase
+{
+    protected function createValidator()
+    {
+        return new UserGroupDoNotExclude(
+            new class () implements TranslatableStringHelperInterface {
+                public function localize(array $translatableStrings): ?string
+                {
+                    return $translatableStrings['fr'];
+                }
+            }
+        );
+    }
+
+    public function testEmptyArrayIsValid(): void
+    {
+        $this->validator->validate([], new \Chill\MainBundle\Validation\Constraint\UserGroupDoNotExclude());
+
+        $this->assertNoViolation();
+    }
+
+    public function testMixedUserGroupAndUsersIsValid(): void
+    {
+        $this->validator->validate(
+            [new User(), new UserGroup()],
+            new \Chill\MainBundle\Validation\Constraint\UserGroupDoNotExclude()
+        );
+
+        $this->assertNoViolation();
+    }
+
+    public function testDifferentExcludeKeysIsValid(): void
+    {
+        $this->validator->validate(
+            [(new UserGroup())->setExcludeKey('A'), (new UserGroup())->setExcludeKey('B')],
+            new \Chill\MainBundle\Validation\Constraint\UserGroupDoNotExclude()
+        );
+
+        $this->assertNoViolation();
+    }
+
+    public function testMultipleGroupsWithEmptyExcludeKeyIsValid(): void
+    {
+        $this->validator->validate(
+            [(new UserGroup())->setExcludeKey(''), (new UserGroup())->setExcludeKey('')],
+            new \Chill\MainBundle\Validation\Constraint\UserGroupDoNotExclude()
+        );
+
+        $this->assertNoViolation();
+    }
+
+    public function testSameExclusionKeyWillRaiseError(): void
+    {
+        $this->validator->validate(
+            [
+                (new UserGroup())->setExcludeKey('A')->setLabel(['fr' => 'Group 1']),
+                (new UserGroup())->setExcludeKey('A')->setLabel(['fr' => 'Group 2']),
+            ],
+            new \Chill\MainBundle\Validation\Constraint\UserGroupDoNotExclude()
+        );
+
+        $this->buildViolation('The groups {{ excluded_groups }} do exclude themselves. Please choose one between them')
+            ->setParameter('excluded_groups', 'Group 1, Group 2')
+            ->setCode('e16c8226-0090-11ef-8560-f7239594db09')
+            ->assertRaised();
+    }
+}
diff --git a/src/Bundle/ChillMainBundle/Validation/Constraint/UserGroupDoNotExclude.php b/src/Bundle/ChillMainBundle/Validation/Constraint/UserGroupDoNotExclude.php
new file mode 100644
index 000000000..5ec688e5b
--- /dev/null
+++ b/src/Bundle/ChillMainBundle/Validation/Constraint/UserGroupDoNotExclude.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\MainBundle\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+#[\Attribute(\Attribute::TARGET_PROPERTY)]
+class UserGroupDoNotExclude extends Constraint
+{
+    public string $message = 'The groups {{ excluded_groups }} do exclude themselves. Please choose one between them';
+    public string $code = 'e16c8226-0090-11ef-8560-f7239594db09';
+
+    public function getTargets()
+    {
+        return [self::PROPERTY_CONSTRAINT];
+    }
+
+    public function validatedBy()
+    {
+        return \Chill\MainBundle\Validation\Validator\UserGroupDoNotExclude::class;
+    }
+}
diff --git a/src/Bundle/ChillMainBundle/Validation/Validator/UserGroupDoNotExclude.php b/src/Bundle/ChillMainBundle/Validation/Validator/UserGroupDoNotExclude.php
new file mode 100644
index 000000000..9bd7167c7
--- /dev/null
+++ b/src/Bundle/ChillMainBundle/Validation/Validator/UserGroupDoNotExclude.php
@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\MainBundle\Validation\Validator;
+
+use Chill\MainBundle\Entity\UserGroup;
+use Chill\MainBundle\Templating\TranslatableStringHelperInterface;
+use Symfony\Component\Validator\Constraint;
+use Symfony\Component\Validator\ConstraintValidator;
+use Symfony\Component\Validator\Exception\UnexpectedTypeException;
+use Symfony\Component\Validator\Exception\UnexpectedValueException;
+
+final class UserGroupDoNotExclude extends ConstraintValidator
+{
+    public function __construct(private readonly TranslatableStringHelperInterface $translatableStringHelper) {}
+
+    public function validate($value, Constraint $constraint)
+    {
+        if (!$constraint instanceof \Chill\MainBundle\Validation\Constraint\UserGroupDoNotExclude) {
+            throw new UnexpectedTypeException($constraint, UserGroupDoNotExclude::class);
+        }
+
+        if (null === $value) {
+            return;
+        }
+
+        if (!is_iterable($value)) {
+            throw new UnexpectedValueException($value, 'iterable');
+        }
+
+        $groups = [];
+
+        foreach ($value as $gr) {
+            if ($gr instanceof UserGroup) {
+                $groups[$gr->getExcludeKey()][] = $gr;
+            }
+        }
+
+        foreach ($groups as $excludeKey => $groupByKey) {
+            if ('' === $excludeKey) {
+                continue;
+            }
+
+            if (1 < count($groupByKey)) {
+                $excludedGroups = implode(
+                    ', ',
+                    array_map(
+                        fn (UserGroup $group) => $this->translatableStringHelper->localize($group->getLabel()),
+                        $groupByKey
+                    )
+                );
+
+                $this->context
+                    ->buildViolation($constraint->message)
+                    ->setCode($constraint->code)
+                    ->setParameters(['excluded_groups' => $excludedGroups])
+                    ->addViolation();
+            }
+        }
+    }
+}
diff --git a/src/Bundle/ChillMainBundle/chill.api.specs.yaml b/src/Bundle/ChillMainBundle/chill.api.specs.yaml
index f37ee723d..958afab07 100644
--- a/src/Bundle/ChillMainBundle/chill.api.specs.yaml
+++ b/src/Bundle/ChillMainBundle/chill.api.specs.yaml
@@ -29,6 +29,42 @@ components:
                     type: string
                 text:
                     type: string
+        UserById:
+            type: object
+            properties:
+                id:
+                    type: integer
+                type:
+                    type: string
+                    enum:
+                        - user
+        UserGroup:
+            type: object
+            properties:
+                id:
+                    type: integer
+                type:
+                    type: string
+                    enum:
+                        - user_group
+                label:
+                    type: object
+                    additionalProperties: true
+                backgroundColor:
+                    type: string
+                foregroundColor:
+                    type: string
+                exclusionKey:
+                    type: string
+        UserGroupById:
+            type: object
+            properties:
+                id:
+                    type: integer
+                type:
+                    type: string
+                    enum:
+                        - user_group
         Center:
             type: object
             properties:
@@ -908,3 +944,19 @@ paths:
                                     $ref: '#/components/schemas/NewsItem'
                 403:
                     description: "Unauthorized"
+    /1.0/main/user-group.json:
+        get:
+            tags:
+                - user-group
+            summary: Return a list of users-groups
+            responses:
+                200:
+                    description: "ok"
+                    content:
+                        application/json:
+                            schema:
+                                type: array
+                                items:
+                                    $ref: '#/components/schemas/UserGroup'
+                403:
+                    description: "Unauthorized"
diff --git a/src/Bundle/ChillMainBundle/config/services/validator.yaml b/src/Bundle/ChillMainBundle/config/services/validator.yaml
index b3b60b9d6..32b8903cc 100644
--- a/src/Bundle/ChillMainBundle/config/services/validator.yaml
+++ b/src/Bundle/ChillMainBundle/config/services/validator.yaml
@@ -3,6 +3,9 @@ services:
         autowire: true
         autoconfigure: true
 
+    Chill\MainBundle\Validation\:
+        resource: '../../Validation'
+
     chill_main.validator_user_circle_consistency:
         class: Chill\MainBundle\Validator\Constraints\Entity\UserCircleConsistencyValidator
         arguments:
diff --git a/src/Bundle/ChillMainBundle/migrations/Version20240422091752.php b/src/Bundle/ChillMainBundle/migrations/Version20240422091752.php
new file mode 100644
index 000000000..960b3cc79
--- /dev/null
+++ b/src/Bundle/ChillMainBundle/migrations/Version20240422091752.php
@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\Migrations\Main;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20240422091752 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Add colors and exclude string to user groups';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->addSql('ALTER TABLE chill_main_user_group ADD backgroundColor TEXT DEFAULT \'#ffffffff\' NOT NULL');
+        $this->addSql('ALTER TABLE chill_main_user_group ADD foregroundColor TEXT DEFAULT \'#000000ff\' NOT NULL');
+        $this->addSql('ALTER TABLE chill_main_user_group ADD excludeKey TEXT DEFAULT \'\' NOT NULL');
+        $this->addSql('ALTER INDEX idx_1e07f044d2112630 RENAME TO IDX_738BC82BD2112630');
+        $this->addSql('ALTER INDEX idx_1e07f044a76ed395 RENAME TO IDX_738BC82BA76ED395');
+    }
+
+    public function down(Schema $schema): void
+    {
+        $this->addSql('ALTER TABLE chill_main_user_group DROP backgroundColor');
+        $this->addSql('ALTER TABLE chill_main_user_group DROP foregroundColor');
+        $this->addSql('ALTER TABLE chill_main_user_group DROP excludeKey');
+        $this->addSql('ALTER INDEX idx_738bc82bd2112630 RENAME TO idx_1e07f044d2112630');
+        $this->addSql('ALTER INDEX idx_738bc82ba76ed395 RENAME TO idx_1e07f044a76ed395');
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/chill.api.specs.yaml b/src/Bundle/ChillTicketBundle/chill.api.specs.yaml
index ce53732ff..5be9ac0c0 100644
--- a/src/Bundle/ChillTicketBundle/chill.api.specs.yaml
+++ b/src/Bundle/ChillTicketBundle/chill.api.specs.yaml
@@ -64,3 +64,100 @@ paths:
                     description: "ACCEPTED"
                 422:
                     description: "UNPROCESSABLE ENTITY"
+
+    /1.0/ticket/{id}/comment/add:
+        post:
+            tags:
+                - ticket
+            summary: Add a comment to an existing ticket
+            parameters:
+                -   name: id
+                    in: path
+                    required: true
+                    description: The ticket id
+                    schema:
+                        type: integer
+                        format: integer
+                        minimum: 1
+            requestBody:
+                required: true
+                content:
+                    application/json:
+                        schema:
+                            type: object
+                            properties:
+                                content:
+                                    type: string
+            responses:
+                201:
+                    description: "ACCEPTED"
+                422:
+                    description: "UNPROCESSABLE ENTITY"
+
+    /1.0/ticket/{id}/addressees/set:
+        post:
+            tags:
+                - ticket
+            summary: Set the addresses for an existing ticket (will replace all the existing addresses)
+            parameters:
+                -   name: id
+                    in: path
+                    required: true
+                    description: The ticket id
+                    schema:
+                        type: integer
+                        format: integer
+                        minimum: 1
+            requestBody:
+                required: true
+                content:
+                    application/json:
+                        schema:
+                            type: object
+                            properties:
+                                addressees:
+                                    type: array
+                                    items:
+                                        oneOf:
+                                            - $ref: '#/components/schemas/UserGroupById'
+                                            - $ref: '#/components/schemas/UserById'
+
+
+            responses:
+                201:
+                    description: "ACCEPTED"
+                422:
+                    description: "UNPROCESSABLE ENTITY"
+
+    /1.0/ticket/{id}/addressee/add:
+        post:
+            tags:
+                - ticket
+            summary: Add an addressee to a ticket, without removing existing ones.
+            parameters:
+                -   name: id
+                    in: path
+                    required: true
+                    description: The ticket id
+                    schema:
+                        type: integer
+                        format: integer
+                        minimum: 1
+            requestBody:
+                required: true
+                content:
+                    application/json:
+                        schema:
+                            type: object
+                            properties:
+                                addressee:
+                                    oneOf:
+                                        - $ref: '#/components/schemas/UserGroupById'
+                                        - $ref: '#/components/schemas/UserById'
+
+
+            responses:
+                201:
+                    description: "ACCEPTED"
+                422:
+                    description: "UNPROCESSABLE ENTITY"
diff --git a/src/Bundle/ChillTicketBundle/src/Action/Ticket/AddAddresseeCommand.php b/src/Bundle/ChillTicketBundle/src/Action/Ticket/AddAddresseeCommand.php
new file mode 100644
index 000000000..d7f9c545f
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Action/Ticket/AddAddresseeCommand.php
@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Action\Ticket;
+
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
+use Symfony\Component\Serializer\Annotation\Groups;
+
+/**
+ * Add a single addressee to the ticket.
+ *
+ * This command is converted into an "SetAddresseesCommand" for handling
+ */
+final readonly class AddAddresseeCommand
+{
+    public function __construct(
+        #[Groups(['read'])]
+        public User|UserGroup $addressee
+    ) {}
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Action/Ticket/AddCommentCommand.php b/src/Bundle/ChillTicketBundle/src/Action/Ticket/AddCommentCommand.php
new file mode 100644
index 000000000..1c009cfc8
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Action/Ticket/AddCommentCommand.php
@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Action\Ticket;
+
+use Symfony\Component\Validator\Constraints as Assert;
+use Symfony\Component\Serializer\Annotation as Serializer;
+
+final readonly class AddCommentCommand
+{
+    public function __construct(
+        #[Assert\NotBlank()]
+        #[Assert\NotNull]
+        #[Serializer\Groups(['write'])]
+        public ?string $content = null,
+    ) {}
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Action/Ticket/Handler/AddCommentCommandHandler.php b/src/Bundle/ChillTicketBundle/src/Action/Ticket/Handler/AddCommentCommandHandler.php
new file mode 100644
index 000000000..66c972c3d
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Action/Ticket/Handler/AddCommentCommandHandler.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Action\Ticket\Handler;
+
+use Chill\TicketBundle\Action\Ticket\AddCommentCommand;
+use Chill\TicketBundle\Entity\Comment;
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+
+final readonly class AddCommentCommandHandler
+{
+    public function __construct(
+        private EntityManagerInterface $entityManager,
+    ) {}
+
+    public function handle(Ticket $ticket, AddCommentCommand $command): void
+    {
+        $comment = new Comment($command->content, $ticket);
+
+        $this->entityManager->persist($comment);
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Action/Ticket/Handler/SetAddresseesCommandHandler.php b/src/Bundle/ChillTicketBundle/src/Action/Ticket/Handler/SetAddresseesCommandHandler.php
new file mode 100644
index 000000000..b2805ed2f
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Action/Ticket/Handler/SetAddresseesCommandHandler.php
@@ -0,0 +1,56 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Action\Ticket\Handler;
+
+use Chill\MainBundle\Entity\User;
+use Chill\TicketBundle\Action\Ticket\SetAddresseesCommand;
+use Chill\TicketBundle\Entity\AddresseeHistory;
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Component\Clock\ClockInterface;
+use Symfony\Component\Security\Core\Security;
+
+final readonly class SetAddresseesCommandHandler
+{
+    public function __construct(
+        private ClockInterface $clock,
+        private EntityManagerInterface $entityManager,
+        private Security $security,
+    ) {}
+
+    public function handle(Ticket $ticket, SetAddresseesCommand $command): void
+    {
+        // remove existing addresses which are not in the new addresses
+        foreach ($ticket->getAddresseeHistories() as $addressHistory) {
+            if (null !== $addressHistory->getEndDate()) {
+                continue;
+            }
+
+            if (!in_array($addressHistory->getAddressee(), $command->addressees, true)) {
+                $addressHistory->setEndDate($this->clock->now());
+                if (($user = $this->security->getUser()) instanceof User) {
+                    $addressHistory->setRemovedBy($user);
+                }
+            }
+        }
+
+        // add new addresses
+        foreach ($command->addressees as $address) {
+            if (in_array($address, $ticket->getCurrentAddressee(), true)) {
+                continue;
+            }
+
+            $history = new AddresseeHistory($address, $this->clock->now(), $ticket);
+            $this->entityManager->persist($history);
+        }
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Action/Ticket/SetAddresseesCommand.php b/src/Bundle/ChillTicketBundle/src/Action/Ticket/SetAddresseesCommand.php
new file mode 100644
index 000000000..e0d474d11
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Action/Ticket/SetAddresseesCommand.php
@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Action\Ticket;
+
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
+use Chill\MainBundle\Validation\Constraint\UserGroupDoNotExclude;
+use Chill\TicketBundle\Entity\Ticket;
+use Symfony\Component\Serializer\Annotation\Groups;
+use Symfony\Component\Validator\Constraints\GreaterThan;
+
+final readonly class SetAddresseesCommand
+{
+    public function __construct(
+        /**
+         * @var list<UserGroup|User>
+         */
+        #[UserGroupDoNotExclude]
+        #[GreaterThan(0)]
+        #[Groups(['read'])]
+        public array $addressees
+    ) {}
+
+    public static function fromAddAddresseeCommand(AddAddresseeCommand $command, Ticket $ticket): self
+    {
+        return new self([
+            $command->addressee,
+            ...$ticket->getCurrentAddressee(),
+        ]);
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Controller/AddCommentController.php b/src/Bundle/ChillTicketBundle/src/Controller/AddCommentController.php
new file mode 100644
index 000000000..157e69698
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Controller/AddCommentController.php
@@ -0,0 +1,68 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Controller;
+
+use Chill\TicketBundle\Action\Ticket\AddCommentCommand;
+use Chill\TicketBundle\Action\Ticket\Handler\AddCommentCommandHandler;
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Component\HttpFoundation\JsonResponse;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
+use Symfony\Component\Routing\Annotation\Route;
+use Symfony\Component\Security\Core\Security;
+use Symfony\Component\Serializer\SerializerInterface;
+use Symfony\Component\Validator\Validator\ValidatorInterface;
+
+final readonly class AddCommentController
+{
+    public function __construct(
+        private Security $security,
+        private SerializerInterface $serializer,
+        private ValidatorInterface $validator,
+        private AddCommentCommandHandler $addCommentCommandHandler,
+        private EntityManagerInterface $entityManager,
+    ) {}
+
+    #[Route('/api/1.0/ticket/{id}/comment/add', name: 'chill_ticket_comment_add', methods: ['POST'])]
+    public function __invoke(Ticket $ticket, Request $request): Response
+    {
+        if (!$this->security->isGranted('ROLE_USER')) {
+            throw new AccessDeniedHttpException('Only user can add ticket comments.');
+        }
+
+        $command = $this->serializer->deserialize($request->getContent(), AddCommentCommand::class, 'json', ['groups' => 'write']);
+
+        $errors = $this->validator->validate($command);
+
+        if (count($errors) > 0) {
+            return new JsonResponse(
+                $this->serializer->serialize($errors, 'json'),
+                Response::HTTP_UNPROCESSABLE_ENTITY,
+                [],
+                true
+            );
+        }
+
+        $this->addCommentCommandHandler->handle($ticket, $command);
+
+        $this->entityManager->flush();
+
+        return new JsonResponse(
+            $this->serializer->serialize($ticket, 'json', ['groups' => 'read']),
+            Response::HTTP_CREATED,
+            [],
+            true
+        );
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Controller/CreateTicketController.php b/src/Bundle/ChillTicketBundle/src/Controller/CreateTicketController.php
index 8a6d8dd32..a3bdf31c8 100644
--- a/src/Bundle/ChillTicketBundle/src/Controller/CreateTicketController.php
+++ b/src/Bundle/ChillTicketBundle/src/Controller/CreateTicketController.php
@@ -15,6 +15,7 @@ use Chill\TicketBundle\Action\Ticket\AssociateByPhonenumberCommand;
 use Chill\TicketBundle\Action\Ticket\Handler\AssociateByPhonenumberCommandHandler;
 use Chill\TicketBundle\Action\Ticket\CreateTicketCommand;
 use Chill\TicketBundle\Action\Ticket\Handler\CreateTicketCommandHandler;
+use Chill\TicketBundle\Repository\TicketRepositoryInterface;
 use Doctrine\ORM\EntityManagerInterface;
 use Symfony\Component\HttpFoundation\RedirectResponse;
 use Symfony\Component\HttpFoundation\Request;
@@ -31,7 +32,8 @@ final readonly class CreateTicketController
         private AssociateByPhonenumberCommandHandler $associateByPhonenumberCommandHandler,
         private Security $security,
         private UrlGeneratorInterface $urlGenerator,
-        private EntityManagerInterface $entityManager
+        private EntityManagerInterface $entityManager,
+        private TicketRepositoryInterface $ticketRepository,
     ) {}
 
     #[Route('{_locale}/ticket/ticket/create')]
@@ -41,6 +43,14 @@ final readonly class CreateTicketController
             throw new AccessDeniedHttpException('Only users are allowed to create tickets.');
         }
 
+        if ('' !== $extId = $request->query->get('extId', '')) {
+            if (null !== $ticket = $this->ticketRepository->findOneByExternalRef($extId)) {
+                return new RedirectResponse(
+                    $this->urlGenerator->generate('chill_ticket_ticket_edit', ['id' => $ticket->getId()])
+                );
+            }
+        }
+
         $createCommand = new CreateTicketCommand($request->query->get('extId', ''));
         $ticket = $this->createTicketCommandHandler->__invoke($createCommand);
 
diff --git a/src/Bundle/ChillTicketBundle/src/Controller/ReplaceMotiveController.php b/src/Bundle/ChillTicketBundle/src/Controller/ReplaceMotiveController.php
index d6f1acf94..8af2773e8 100644
--- a/src/Bundle/ChillTicketBundle/src/Controller/ReplaceMotiveController.php
+++ b/src/Bundle/ChillTicketBundle/src/Controller/ReplaceMotiveController.php
@@ -59,6 +59,11 @@ final readonly class ReplaceMotiveController
 
         $this->entityManager->flush();
 
-        return new JsonResponse(null, Response::HTTP_CREATED);
+        return new JsonResponse(
+            $this->serializer->serialize($ticket, 'json', ['groups' => 'read']),
+            Response::HTTP_CREATED,
+            [],
+            true
+        );
     }
 }
diff --git a/src/Bundle/ChillTicketBundle/src/Controller/SetAddresseesController.php b/src/Bundle/ChillTicketBundle/src/Controller/SetAddresseesController.php
new file mode 100644
index 000000000..9fa6dc366
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Controller/SetAddresseesController.php
@@ -0,0 +1,85 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Controller;
+
+use Chill\TicketBundle\Action\Ticket\AddAddresseeCommand;
+use Chill\TicketBundle\Action\Ticket\Handler\SetAddresseesCommandHandler;
+use Chill\TicketBundle\Action\Ticket\SetAddresseesCommand;
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Component\HttpFoundation\JsonResponse;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
+use Symfony\Component\Routing\Annotation\Route;
+use Symfony\Component\Security\Core\Security;
+use Symfony\Component\Serializer\Normalizer\AbstractNormalizer;
+use Symfony\Component\Serializer\SerializerInterface;
+use Symfony\Component\Validator\Validator\ValidatorInterface;
+
+final readonly class SetAddresseesController
+{
+    public function __construct(
+        private Security $security,
+        private EntityManagerInterface $entityManager,
+        private SerializerInterface $serializer,
+        private SetAddresseesCommandHandler $addressesCommandHandler,
+        private ValidatorInterface $validator,
+    ) {}
+
+    #[Route('/api/1.0/ticket/{id}/addressees/set', methods: ['POST'])]
+    public function setAddressees(Ticket $ticket, Request $request): Response
+    {
+        if (!$this->security->isGranted('ROLE_USER')) {
+            throw new AccessDeniedHttpException('Only users can set addressees.');
+        }
+
+        $command = $this->serializer->deserialize($request->getContent(), SetAddresseesCommand::class, 'json', [AbstractNormalizer::GROUPS => ['read']]);
+
+        return $this->registerSetAddressees($command, $ticket);
+    }
+
+    #[Route('/api/1.0/ticket/{id}/addressee/add', methods: ['POST'])]
+    public function addAddressee(Ticket $ticket, Request $request): Response
+    {
+        if (!$this->security->isGranted('ROLE_USER')) {
+            throw new AccessDeniedHttpException('Only users can add addressees.');
+        }
+
+        $command = $this->serializer->deserialize($request->getContent(), AddAddresseeCommand::class, 'json', [AbstractNormalizer::GROUPS => ['read']]);
+
+        return $this->registerSetAddressees(SetAddresseesCommand::fromAddAddresseeCommand($command, $ticket), $ticket);
+    }
+
+    private function registerSetAddressees(SetAddresseesCommand $command, Ticket $ticket): Response
+    {
+        if (0 < count($errors = $this->validator->validate($command))) {
+            return new JsonResponse(
+                $this->serializer->serialize($errors, 'json'),
+                Response::HTTP_UNPROCESSABLE_ENTITY,
+                [],
+                true
+            );
+        }
+
+        $this->addressesCommandHandler->handle($ticket, $command);
+
+        $this->entityManager->flush();
+
+        return new JsonResponse(
+            $this->serializer->serialize($ticket, 'json', ['groups' => 'read']),
+            Response::HTTP_OK,
+            [],
+            true,
+        );
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Entity/AddresseeHistory.php b/src/Bundle/ChillTicketBundle/src/Entity/AddresseeHistory.php
index 3939a24c3..2717df2a5 100644
--- a/src/Bundle/ChillTicketBundle/src/Entity/AddresseeHistory.php
+++ b/src/Bundle/ChillTicketBundle/src/Entity/AddresseeHistory.php
@@ -18,9 +18,11 @@ use Chill\MainBundle\Doctrine\Model\TrackUpdateTrait;
 use Chill\MainBundle\Entity\User;
 use Chill\MainBundle\Entity\UserGroup;
 use Doctrine\ORM\Mapping as ORM;
+use Symfony\Component\Serializer\Annotation as Serializer;
 
 #[ORM\Entity()]
 #[ORM\Table(name: 'addressee_history', schema: 'chill_ticket')]
+#[Serializer\DiscriminatorMap(typeProperty: 'type', mapping: ['ticket_addressee_history' => AddresseeHistory::class])]
 class AddresseeHistory implements TrackUpdateInterface, TrackCreationInterface
 {
     use TrackCreationTrait;
@@ -29,6 +31,7 @@ class AddresseeHistory implements TrackUpdateInterface, TrackCreationInterface
     #[ORM\Id]
     #[ORM\Column(type: \Doctrine\DBAL\Types\Types::INTEGER, nullable: false)]
     #[ORM\GeneratedValue(strategy: 'AUTO')]
+    #[Serializer\Groups(['read'])]
     private ?int $id = null;
 
     #[ORM\ManyToOne(targetEntity: User::class)]
@@ -39,11 +42,19 @@ class AddresseeHistory implements TrackUpdateInterface, TrackCreationInterface
     #[ORM\JoinColumn(nullable: true)]
     private ?UserGroup $addresseeGroup = null;
 
+    #[ORM\Column(type: \Doctrine\DBAL\Types\Types::DATETIME_IMMUTABLE, nullable: true, options: ['default' => 'null'])]
+    #[Serializer\Groups(['read'])]
     private ?\DateTimeImmutable $endDate = null;
 
+    #[ORM\ManyToOne(targetEntity: User::class)]
+    #[ORM\JoinColumn(nullable: true)]
+    #[Serializer\Groups(['read'])]
+    private ?User $removedBy = null;
+
     public function __construct(
         User|UserGroup $addressee,
         #[ORM\Column(type: \Doctrine\DBAL\Types\Types::DATETIME_IMMUTABLE, nullable: false)]
+        #[Serializer\Groups(['read'])]
         private \DateTimeImmutable $startDate,
         #[ORM\ManyToOne(targetEntity: Ticket::class)]
         #[ORM\JoinColumn(nullable: false)]
@@ -54,8 +65,11 @@ class AddresseeHistory implements TrackUpdateInterface, TrackCreationInterface
         } else {
             $this->addresseeGroup = $addressee;
         }
+
+        $this->ticket->addAddresseeHistory($this);
     }
 
+    #[Serializer\Groups(['read'])]
     public function getAddressee(): UserGroup|User
     {
         if (null !== $this->addresseeGroup) {
@@ -94,4 +108,23 @@ class AddresseeHistory implements TrackUpdateInterface, TrackCreationInterface
     {
         return $this->ticket;
     }
+
+    public function getRemovedBy(): ?User
+    {
+        return $this->removedBy;
+    }
+
+    public function setRemovedBy(?User $removedBy): self
+    {
+        $this->removedBy = $removedBy;
+
+        return $this;
+    }
+
+    public function setEndDate(?\DateTimeImmutable $endDate): self
+    {
+        $this->endDate = $endDate;
+
+        return $this;
+    }
 }
diff --git a/src/Bundle/ChillTicketBundle/src/Entity/Comment.php b/src/Bundle/ChillTicketBundle/src/Entity/Comment.php
index d62e6d8b4..8e11ff489 100644
--- a/src/Bundle/ChillTicketBundle/src/Entity/Comment.php
+++ b/src/Bundle/ChillTicketBundle/src/Entity/Comment.php
@@ -17,9 +17,11 @@ use Chill\MainBundle\Doctrine\Model\TrackUpdateInterface;
 use Chill\MainBundle\Doctrine\Model\TrackUpdateTrait;
 use Doctrine\ORM\Mapping as ORM;
 use Doctrine\ORM\Mapping\JoinColumn;
+use Symfony\Component\Serializer\Annotation as Serializer;
 
 #[ORM\Entity()]
 #[ORM\Table(name: 'comment', schema: 'chill_ticket')]
+#[Serializer\DiscriminatorMap(typeProperty: 'type', mapping: ['ticket_comment' => Comment::class])]
 class Comment implements TrackCreationInterface, TrackUpdateInterface
 {
     use TrackCreationTrait;
@@ -28,15 +30,19 @@ class Comment implements TrackCreationInterface, TrackUpdateInterface
     #[ORM\Id]
     #[ORM\Column(type: \Doctrine\DBAL\Types\Types::INTEGER, nullable: false)]
     #[ORM\GeneratedValue(strategy: 'AUTO')]
+    #[Serializer\Groups(['read'])]
     private ?int $id = null;
 
     public function __construct(
+        #[ORM\Column(type: \Doctrine\DBAL\Types\Types::TEXT, nullable: false, options: ['default' => ''])]
+        #[Serializer\Groups(['read'])]
+        private string $content,
         #[ORM\ManyToOne(targetEntity: Ticket::class, inversedBy: 'comments')]
         #[JoinColumn(nullable: false)]
         private Ticket $ticket,
-        #[ORM\Column(type: \Doctrine\DBAL\Types\Types::TEXT, nullable: false, options: ['default' => ''])]
-        private string $content = ''
-    ) {}
+    ) {
+        $ticket->addComment($this);
+    }
 
     public function getId(): ?int
     {
diff --git a/src/Bundle/ChillTicketBundle/src/Entity/PersonHistory.php b/src/Bundle/ChillTicketBundle/src/Entity/PersonHistory.php
index 57a9809e2..927ea978f 100644
--- a/src/Bundle/ChillTicketBundle/src/Entity/PersonHistory.php
+++ b/src/Bundle/ChillTicketBundle/src/Entity/PersonHistory.php
@@ -84,4 +84,11 @@ class PersonHistory implements TrackCreationInterface
     {
         return $this->removedBy;
     }
+
+    public function setEndDate(?\DateTimeImmutable $endDate): self
+    {
+        $this->endDate = $endDate;
+
+        return $this;
+    }
 }
diff --git a/src/Bundle/ChillTicketBundle/src/Entity/Ticket.php b/src/Bundle/ChillTicketBundle/src/Entity/Ticket.php
index de369379b..04cfe828b 100644
--- a/src/Bundle/ChillTicketBundle/src/Entity/Ticket.php
+++ b/src/Bundle/ChillTicketBundle/src/Entity/Ticket.php
@@ -104,21 +104,40 @@ class Ticket implements TrackCreationInterface, TrackUpdateInterface
             ->getValues();
     }
 
+    /**
+     * @internal use @see{Comment::__construct} instead
+     */
+    public function addComment(Comment $comment): void
+    {
+        $this->comments->add($comment);
+    }
+
     /**
      * Add a PersonHistory.
      *
-     * This method should not be used, use @see{PersonHistory::__construct()} insted.
+     * @internal use @see{PersonHistory::__construct} instead
      */
     public function addPersonHistory(PersonHistory $personHistory): void
     {
         $this->personHistories->add($personHistory);
     }
 
+    /**
+     * @internal use @see{MotiveHistory::__construct} instead
+     */
     public function addMotiveHistory(MotiveHistory $motiveHistory): void
     {
         $this->motiveHistories->add($motiveHistory);
     }
 
+    /**
+     * @internal use @see{AddresseHistory::__construct} instead
+     */
+    public function addAddresseeHistory(AddresseeHistory $addresseeHistory): void
+    {
+        $this->addresseeHistory->add($addresseeHistory);
+    }
+
     /**
      * @return list<UserGroup|User>
      */
@@ -184,4 +203,12 @@ class Ticket implements TrackCreationInterface, TrackUpdateInterface
     {
         return $this->personHistories;
     }
+
+    /**
+     * @return ReadableCollection<int, AddresseeHistory>
+     */
+    public function getAddresseeHistories(): ReadableCollection
+    {
+        return $this->addresseeHistory;
+    }
 }
diff --git a/src/Bundle/ChillTicketBundle/src/Repository/TicketRepository.php b/src/Bundle/ChillTicketBundle/src/Repository/TicketRepository.php
new file mode 100644
index 000000000..d4301585a
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Repository/TicketRepository.php
@@ -0,0 +1,56 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Repository;
+
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+use Doctrine\Persistence\ObjectRepository;
+
+final readonly class TicketRepository implements TicketRepositoryInterface
+{
+    private ObjectRepository $repository;
+
+    public function __construct(EntityManagerInterface $objectManager)
+    {
+        $this->repository = $objectManager->getRepository($this->getClassName());
+    }
+
+    public function find($id): ?Ticket
+    {
+        return $this->repository->find($id);
+    }
+
+    public function findAll(): array
+    {
+        return $this->repository->findAll();
+    }
+
+    public function findBy(array $criteria, ?array $orderBy = null, ?int $limit = null, ?int $offset = null): array
+    {
+        return $this->repository->findBy($criteria, $orderBy, $limit, $offset);
+    }
+
+    public function findOneBy(array $criteria): ?Ticket
+    {
+        return $this->repository->findOneBy($criteria);
+    }
+
+    public function getClassName()
+    {
+        return Ticket::class;
+    }
+
+    public function findOneByExternalRef(string $extId): ?Ticket
+    {
+        return $this->repository->findOneBy(['externalRef' => $extId]);
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Repository/TicketRepositoryInterface.php b/src/Bundle/ChillTicketBundle/src/Repository/TicketRepositoryInterface.php
new file mode 100644
index 000000000..0b2cb4d66
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Repository/TicketRepositoryInterface.php
@@ -0,0 +1,23 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Repository;
+
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\Persistence\ObjectRepository;
+
+/**
+ * @extends ObjectRepository<Ticket>
+ */
+interface TicketRepositoryInterface extends ObjectRepository
+{
+    public function findOneByExternalRef(string $extId): ?Ticket;
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Resources/public/types.ts b/src/Bundle/ChillTicketBundle/src/Resources/public/types.ts
index b0c6a37df..0bcd1ecbb 100644
--- a/src/Bundle/ChillTicketBundle/src/Resources/public/types.ts
+++ b/src/Bundle/ChillTicketBundle/src/Resources/public/types.ts
@@ -1,4 +1,10 @@
-import {DateTime, TranslatableString, User} from "../../../../ChillMainBundle/Resources/public/types";
+import {
+    DateTime,
+    TranslatableString,
+    User,
+    UserGroup,
+    UserGroupOrUser
+} from "../../../../ChillMainBundle/Resources/public/types";
 import {Person} from "../../../../ChillPersonBundle/Resources/public/types";
 
 export interface Motive {
@@ -36,17 +42,43 @@ interface MotiveHistory {
     createdAt: DateTime|null,
 }
 
-interface AddPersonEvent extends TicketHistory<"add_person", PersonHistory> {};
-interface SetMotiveEvent extends TicketHistory<"set_motive", MotiveHistory> {};
+interface Comment {
+    type: "ticket_comment",
+    id: number,
+    content: string,
+    createdBy: User|null,
+    createdAt: DateTime|null,
+    updatedBy: User|null,
+    updatedAt: DateTime|null,
+}
 
-type TicketHistoryLine = AddPersonEvent | SetMotiveEvent;
+interface AddresseeHistory {
+    type: "ticket_addressee_history",
+    id: number,
+    startDate: DateTime|null,
+    addressee: UserGroupOrUser,
+    endDate: DateTime|null,
+    removedBy: User|null,
+    createdBy: User|null,
+    createdAt: DateTime|null,
+    updatedBy: User|null,
+    updatedAt: DateTime|null,
+}
+
+interface AddPersonEvent extends TicketHistory<"add_person", PersonHistory> {};
+interface AddCommentEvent extends TicketHistory<"add_comment", Comment> {};
+interface SetMotiveEvent extends TicketHistory<"set_motive", MotiveHistory> {};
+interface AddAddressee extends TicketHistory<"add_addressee", AddresseeHistory> {};
+
+type TicketHistoryLine = AddPersonEvent | AddCommentEvent | SetMotiveEvent | AddAddressee;
 
 export interface Ticket {
-    type: "ticket_ticket"
-    id: number
-    externalRef: string
-    currentPersons: Person[]
-    currentMotive: null|Motive
+    type: "ticket_ticket",
+    id: number,
+    externalRef: string,
+    currentAddressees: UserGroupOrUser[],
+    currentPersons: Person[],
+    currentMotive: null|Motive,
     history: TicketHistoryLine[],
 }
 
diff --git a/src/Bundle/ChillTicketBundle/src/Serializer/Normalizer/SetAddresseesCommandDenormalizer.php b/src/Bundle/ChillTicketBundle/src/Serializer/Normalizer/SetAddresseesCommandDenormalizer.php
new file mode 100644
index 000000000..d97ca5d92
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Serializer/Normalizer/SetAddresseesCommandDenormalizer.php
@@ -0,0 +1,56 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Serializer\Normalizer;
+
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
+use Chill\TicketBundle\Action\Ticket\SetAddresseesCommand;
+use Symfony\Component\Serializer\Exception\UnexpectedValueException;
+use Symfony\Component\Serializer\Normalizer\DenormalizerAwareInterface;
+use Symfony\Component\Serializer\Normalizer\DenormalizerAwareTrait;
+use Symfony\Component\Serializer\Normalizer\DenormalizerInterface;
+
+final class SetAddresseesCommandDenormalizer implements DenormalizerInterface, DenormalizerAwareInterface
+{
+    use DenormalizerAwareTrait;
+
+    public function denormalize($data, string $type, ?string $format = null, array $context = [])
+    {
+        if (null === $data) {
+            return null;
+        }
+
+        if (!array_key_exists('addressees', $data)) {
+            throw new UnexpectedValueException("key 'addressees' does exists");
+        }
+
+        if (!is_array($data['addressees'])) {
+            throw new UnexpectedValueException("key 'addressees' must be an array");
+        }
+
+        $addresses = [];
+        foreach ($data['addressees'] as $address) {
+            $addresses[] = match ($address['type'] ?? '') {
+                'user_group' => $this->denormalizer->denormalize($address, UserGroup::class, $format, $context),
+                'user' => $this->denormalizer->denormalize($address, User::class, $format, $context),
+                default => throw new UnexpectedValueException('the type is not set or not supported')
+            };
+        }
+
+        return new SetAddresseesCommand($addresses);
+    }
+
+    public function supportsDenormalization($data, string $type, ?string $format = null)
+    {
+        return SetAddresseesCommand::class === $type && 'json' === $format;
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Serializer/Normalizer/TicketNormalizer.php b/src/Bundle/ChillTicketBundle/src/Serializer/Normalizer/TicketNormalizer.php
index c69ac5a7f..f7aff602b 100644
--- a/src/Bundle/ChillTicketBundle/src/Serializer/Normalizer/TicketNormalizer.php
+++ b/src/Bundle/ChillTicketBundle/src/Serializer/Normalizer/TicketNormalizer.php
@@ -11,6 +11,8 @@ declare(strict_types=1);
 
 namespace Chill\TicketBundle\Serializer\Normalizer;
 
+use Chill\TicketBundle\Entity\AddresseeHistory;
+use Chill\TicketBundle\Entity\Comment;
 use Chill\TicketBundle\Entity\MotiveHistory;
 use Chill\TicketBundle\Entity\PersonHistory;
 use Chill\TicketBundle\Entity\Ticket;
@@ -69,6 +71,33 @@ final class TicketNormalizer implements NormalizerInterface, NormalizerAwareInte
                 ],
                 $ticket->getPersonHistories()->toArray(),
             ),
+            ...array_map(
+                fn (Comment $comment) => [
+                    'event_type' => 'add_comment',
+                    'at' => $comment->getCreatedAt(),
+                    'by' => $comment->getCreatedBy(),
+                    'data' => $comment,
+                ],
+                $ticket->getComments()->toArray(),
+            ),
+            ...array_map(
+                fn (AddresseeHistory $history) => [
+                    'event_type' => 'add_addressee',
+                    'at' => $history->getStartDate(),
+                    'by' => $history->getCreatedBy(),
+                    'data' => $history,
+                ],
+                $ticket->getAddresseeHistories()->toArray(),
+            ),
+            ...array_map(
+                fn (AddresseeHistory $history) => [
+                    'event_type' => 'remove_addressee',
+                    'at' => $history->getStartDate(),
+                    'by' => $history->getRemovedBy(),
+                    'data' => $history,
+                ],
+                $ticket->getAddresseeHistories()->filter(fn (AddresseeHistory $history) => null !== $history->getEndDate())->toArray()
+            ),
         ];
 
         usort(
diff --git a/src/Bundle/ChillTicketBundle/src/config/services.yaml b/src/Bundle/ChillTicketBundle/src/config/services.yaml
index 490e215c4..4b662ecdc 100644
--- a/src/Bundle/ChillTicketBundle/src/config/services.yaml
+++ b/src/Bundle/ChillTicketBundle/src/config/services.yaml
@@ -3,16 +3,21 @@ services:
         autoconfigure: true
         autowire: true
 
+    Chill\TicketBundle\Action\Ticket\Handler\:
+        resource: '../Action/Ticket/Handler/'
+
     Chill\TicketBundle\Controller\:
         resource: '../Controller/'
         tags:
             - controller.service_arguments
 
-    Chill\TicketBundle\Action\Ticket\Handler\:
-        resource: '../Action/Ticket/Handler/'
+    Chill\TicketBundle\Repository\:
+        resource: '../Repository/'
 
     Chill\TicketBundle\Serializer\:
         resource: '../Serializer/'
 
-    Chill\TicketBundle\DataFixtures\:
-        resource: '../DataFixtures/'
+when@dev:
+    services:
+        Chill\TicketBundle\DataFixtures\:
+            resource: '../DataFixtures/'
diff --git a/src/Bundle/ChillTicketBundle/src/migrations/Version20240423212824.php b/src/Bundle/ChillTicketBundle/src/migrations/Version20240423212824.php
new file mode 100644
index 000000000..3c025d763
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/migrations/Version20240423212824.php
@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\Migrations\Ticket;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20240423212824 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Add endDate and removedBy columns on addressee history (ticket)';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->addSql('ALTER TABLE chill_ticket.addressee_history ADD endDate TIMESTAMP(0) WITHOUT TIME ZONE DEFAULT null');
+        $this->addSql('ALTER TABLE chill_ticket.addressee_history ADD removedBy_id INT DEFAULT NULL');
+        $this->addSql('COMMENT ON COLUMN chill_ticket.addressee_history.endDate IS \'(DC2Type:datetime_immutable)\'');
+        $this->addSql('ALTER TABLE chill_ticket.addressee_history ADD CONSTRAINT FK_434EBDBDB8346CCF FOREIGN KEY (removedBy_id) REFERENCES users (id) NOT DEFERRABLE INITIALLY IMMEDIATE');
+        $this->addSql('CREATE INDEX IDX_434EBDBDB8346CCF ON chill_ticket.addressee_history (removedBy_id)');
+    }
+
+    public function down(Schema $schema): void
+    {
+        $this->addSql('ALTER TABLE chill_ticket.addressee_history DROP CONSTRAINT FK_434EBDBDB8346CCF');
+        $this->addSql('DROP INDEX chill_ticket.IDX_434EBDBDB8346CCF');
+        $this->addSql('ALTER TABLE chill_ticket.addressee_history DROP endDate');
+        $this->addSql('ALTER TABLE chill_ticket.addressee_history DROP removedBy_id');
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/tests/Action/Ticket/Handler/AddCommentCommandHandlerTest.php b/src/Bundle/ChillTicketBundle/tests/Action/Ticket/Handler/AddCommentCommandHandlerTest.php
new file mode 100644
index 000000000..5ff18b436
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/tests/Action/Ticket/Handler/AddCommentCommandHandlerTest.php
@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Tests\Action\Ticket\Handler;
+
+use Chill\TicketBundle\Action\Ticket\AddCommentCommand;
+use Chill\TicketBundle\Action\Ticket\Handler\AddCommentCommandHandler;
+use Chill\TicketBundle\Entity\Comment;
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+use PHPUnit\Framework\TestCase;
+use Prophecy\Argument;
+use Prophecy\PhpUnit\ProphecyTrait;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+class AddCommentCommandHandlerTest extends TestCase
+{
+    use ProphecyTrait;
+
+    public function testAddComment(): void
+    {
+        $handler = $this->buildCommand();
+
+        $ticket = new Ticket();
+        $command = new AddCommentCommand(content: 'test');
+
+        $handler->handle($ticket, $command);
+
+        self::assertCount(1, $ticket->getComments());
+        self::assertEquals('test', $ticket->getComments()[0]->getContent());
+    }
+
+    private function buildCommand(): AddCommentCommandHandler
+    {
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+        $entityManager->persist(Argument::type(Comment::class))->shouldBeCalled();
+
+        return new AddCommentCommandHandler($entityManager->reveal());
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/tests/Action/Ticket/Handler/SetAddressesCommandHandlerTest.php b/src/Bundle/ChillTicketBundle/tests/Action/Ticket/Handler/SetAddressesCommandHandlerTest.php
new file mode 100644
index 000000000..cef1ae153
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/tests/Action/Ticket/Handler/SetAddressesCommandHandlerTest.php
@@ -0,0 +1,122 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Tests\Action\Ticket\Handler;
+
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
+use Chill\TicketBundle\Action\Ticket\Handler\SetAddresseesCommandHandler;
+use Chill\TicketBundle\Action\Ticket\SetAddresseesCommand;
+use Chill\TicketBundle\Entity\AddresseeHistory;
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+use PHPUnit\Framework\TestCase;
+use Prophecy\Argument;
+use Prophecy\PhpUnit\ProphecyTrait;
+use Symfony\Component\Clock\MockClock;
+use Symfony\Component\Security\Core\Security;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+final class SetAddressesCommandHandlerTest extends TestCase
+{
+    use ProphecyTrait;
+
+    public function testHandleOnEmptyAddresses(): void
+    {
+        $ticket = new Ticket();
+        $command = new SetAddresseesCommand([$user1 = new User(), $group1 = new UserGroup()]);
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+        $entityManager->persist(Argument::that(function ($arg) use ($user1) {
+            return $arg instanceof AddresseeHistory && $arg->getAddressee() === $user1;
+        }))->shouldBeCalledOnce();
+        $entityManager->persist(Argument::that(function ($arg) use ($group1) {
+            return $arg instanceof AddresseeHistory && $arg->getAddressee() === $group1;
+        }))->shouldBeCalledOnce();
+
+        $handler = $this->buildHandler($entityManager->reveal());
+
+        $handler->handle($ticket, $command);
+
+        self::assertCount(2, $ticket->getCurrentAddressee());
+    }
+
+    public function testHandleExistingUserIsNotRemovedNorCreatingDouble(): void
+    {
+        $ticket = new Ticket();
+        $user = new User();
+        $history = new AddresseeHistory($user, new \DateTimeImmutable('1 month ago'), $ticket);
+        $command = new SetAddresseesCommand([$user]);
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+        $entityManager->persist(Argument::that(function ($arg) use ($user) {
+            return $arg instanceof AddresseeHistory && $arg->getAddressee() === $user;
+        }))->shouldNotBeCalled();
+
+        $handler = $this->buildHandler($entityManager->reveal());
+
+        $handler->handle($ticket, $command);
+
+        self::assertNull($history->getEndDate());
+        self::assertCount(1, $ticket->getCurrentAddressee());
+    }
+
+    public function testHandleRemoveExistingAddressee(): void
+    {
+        $ticket = new Ticket();
+        $user = new User();
+        $group = new UserGroup();
+        $history = new AddresseeHistory($user, new \DateTimeImmutable('1 month ago'), $ticket);
+        $command = new SetAddresseesCommand([$group]);
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+        $entityManager->persist(Argument::that(function ($arg) use ($group) {
+            return $arg instanceof AddresseeHistory && $arg->getAddressee() === $group;
+        }))->shouldBeCalled();
+
+        $handler = $this->buildHandler($entityManager->reveal());
+
+        $handler->handle($ticket, $command);
+
+        self::assertNotNull($history->getEndDate());
+        self::assertContains($group, $ticket->getCurrentAddressee());
+    }
+
+    public function testAddingDoublingAddresseeDoesNotCreateDoubleHistories(): void
+    {
+        $ticket = new Ticket();
+        $group = new UserGroup();
+        $command = new SetAddresseesCommand([$group, $group]);
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+        $entityManager->persist(Argument::that(function ($arg) use ($group) {
+            return $arg instanceof AddresseeHistory && $arg->getAddressee() === $group;
+        }))->shouldBeCalledOnce();
+
+        $handler = $this->buildHandler($entityManager->reveal());
+
+        $handler->handle($ticket, $command);
+
+        self::assertCount(1, $ticket->getCurrentAddressee());
+    }
+
+    private function buildHandler(EntityManagerInterface $entityManager): SetAddresseesCommandHandler
+    {
+        $security = $this->prophesize(Security::class);
+        $security->getUser()->willReturn(new User());
+
+        return new SetAddresseesCommandHandler(new MockClock(), $entityManager, $security->reveal());
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/tests/Controller/AddCommentControllerTest.php b/src/Bundle/ChillTicketBundle/tests/Controller/AddCommentControllerTest.php
new file mode 100644
index 000000000..2826c360d
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/tests/Controller/AddCommentControllerTest.php
@@ -0,0 +1,104 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Tests\Controller;
+
+use Chill\TicketBundle\Action\Ticket\Handler\AddCommentCommandHandler;
+use Chill\TicketBundle\Controller\AddCommentController;
+use Chill\TicketBundle\Entity\Comment;
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+use Prophecy\Argument;
+use Prophecy\PhpUnit\ProphecyTrait;
+use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\Security\Core\Security;
+use Symfony\Component\Serializer\SerializerInterface;
+use Symfony\Component\Validator\Validator\ValidatorInterface;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+class AddCommentControllerTest extends KernelTestCase
+{
+    use ProphecyTrait;
+
+    private SerializerInterface $serializer;
+    private ValidatorInterface $validator;
+
+    protected function setUp(): void
+    {
+        self::bootKernel();
+        $this->validator = self::getContainer()->get(ValidatorInterface::class);
+        $this->serializer = self::getContainer()->get(SerializerInterface::class);
+    }
+
+    public function testAddComment(): void
+    {
+        $controller = $this->buildController(willFlush: true);
+
+        $ticket = new Ticket();
+        $request = new Request(content: <<<'JSON'
+            {"content":  "test"}
+            JSON);
+
+        $response = $controller->__invoke($ticket, $request);
+
+        self::assertEquals(201, $response->getStatusCode());
+    }
+
+    public function testAddCommentWithBlankContent(): void
+    {
+        $controller = $this->buildController(willFlush: false);
+
+        $ticket = new Ticket();
+        $request = new Request(content: <<<'JSON'
+            {"content":  ""}
+            JSON);
+
+        $response = $controller->__invoke($ticket, $request);
+
+        self::assertEquals(422, $response->getStatusCode());
+
+        $request = new Request(content: <<<'JSON'
+            {"content":  null}
+            JSON);
+
+        $response = $controller->__invoke($ticket, $request);
+
+        self::assertEquals(422, $response->getStatusCode());
+    }
+
+    private function buildController(bool $willFlush): AddCommentController
+    {
+        $security = $this->prophesize(Security::class);
+        $security->isGranted('ROLE_USER')->willReturn(true);
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+
+        if ($willFlush) {
+            $entityManager->persist(Argument::type(Comment::class))->shouldBeCalled();
+            $entityManager->flush()->shouldBeCalled();
+        }
+
+        $commandHandler = new AddCommentCommandHandler($entityManager->reveal());
+
+        return new AddCommentController(
+            $security->reveal(),
+            $this->serializer,
+            $this->validator,
+            $commandHandler,
+            $entityManager->reveal(),
+        );
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/tests/Controller/SetAddresseesControllerTest.php b/src/Bundle/ChillTicketBundle/tests/Controller/SetAddresseesControllerTest.php
new file mode 100644
index 000000000..af0d48e87
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/tests/Controller/SetAddresseesControllerTest.php
@@ -0,0 +1,212 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Tests\Controller;
+
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
+use Chill\TicketBundle\Action\Ticket\Handler\SetAddresseesCommandHandler;
+use Chill\TicketBundle\Action\Ticket\SetAddresseesCommand;
+use Chill\TicketBundle\Controller\SetAddresseesController;
+use Chill\TicketBundle\Entity\AddresseeHistory;
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+use Prophecy\Argument;
+use Prophecy\PhpUnit\ProphecyTrait;
+use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
+use Symfony\Component\Clock\MockClock;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\Security\Core\Security;
+use Symfony\Component\Serializer\SerializerInterface;
+use Symfony\Component\Validator\ConstraintViolation;
+use Symfony\Component\Validator\ConstraintViolationList;
+use Symfony\Component\Validator\Validator\ValidatorInterface;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+class SetAddresseesControllerTest extends KernelTestCase
+{
+    use ProphecyTrait;
+
+    private SerializerInterface $serializer;
+
+    protected function setUp(): void
+    {
+        self::bootKernel();
+        $this->serializer = self::getContainer()->get(SerializerInterface::class);
+    }
+
+    /**
+     * @dataProvider getContentData
+     */
+    public function testSetAddresseesWithValidData(array $bodyAsArray): void
+    {
+        $controller = $this->buildController(true, true);
+        $request = new Request(content: json_encode(['addressees' => $bodyAsArray], JSON_THROW_ON_ERROR, 512));
+        $ticket = new Ticket();
+
+        $response = $controller->setAddressees($ticket, $request);
+
+        self::assertEquals(200, $response->getStatusCode());
+
+        $asArray = json_decode($response->getContent(), true, 512, JSON_THROW_ON_ERROR);
+        self::assertIsArray($asArray);
+        self::assertArrayHasKey('type', $asArray);
+        self::assertEquals('ticket_ticket', $asArray['type']);
+    }
+
+    /**
+     * @dataProvider getContentData
+     */
+    public function testSetAddresseesWithInvalidData(array $bodyAsArray): void
+    {
+        $controller = $this->buildController(false, false);
+        $request = new Request(content: json_encode(['addressees' => $bodyAsArray], JSON_THROW_ON_ERROR, 512));
+        $ticket = new Ticket();
+
+        $response = $controller->setAddressees($ticket, $request);
+
+        self::assertEquals(422, $response->getStatusCode());
+
+        $asArray = json_decode($response->getContent(), true, 512, JSON_THROW_ON_ERROR);
+        self::assertIsArray($asArray);
+        self::arrayHasKey('violations', $asArray);
+        self::assertGreaterThan(0, count($asArray['violations']));
+    }
+
+    /**
+     * @dataProvider getContentDataUnique
+     */
+    public function testAddAddresseeWithValidData(array $bodyAsArray): void
+    {
+        $controller = $this->buildController(true, true);
+        $request = new Request(content: json_encode(['addressee' => $bodyAsArray], JSON_THROW_ON_ERROR, 512));
+        $ticket = new Ticket();
+
+        $response = $controller->addAddressee($ticket, $request);
+
+        self::assertEquals(200, $response->getStatusCode());
+
+        $asArray = json_decode($response->getContent(), true, 512, JSON_THROW_ON_ERROR);
+        self::assertIsArray($asArray);
+        self::assertArrayHasKey('type', $asArray);
+        self::assertEquals('ticket_ticket', $asArray['type']);
+    }
+
+    /**
+     * @throws \JsonException
+     *
+     * @dataProvider getContentDataUnique
+     */
+    public function testAddAddresseeWithInvalidData(array $bodyAsArray): void
+    {
+        $controller = $this->buildController(false, false);
+        $request = new Request(content: json_encode(['addressee' => $bodyAsArray], JSON_THROW_ON_ERROR, 512));
+        $ticket = new Ticket();
+
+        $response = $controller->addAddressee($ticket, $request);
+
+        self::assertEquals(422, $response->getStatusCode());
+
+        $asArray = json_decode($response->getContent(), true, 512, JSON_THROW_ON_ERROR);
+        self::assertIsArray($asArray);
+        self::arrayHasKey('violations', $asArray);
+        self::assertGreaterThan(0, count($asArray['violations']));
+    }
+
+    public static function getContentDataUnique(): iterable
+    {
+        $entityManager = self::getContainer()->get(EntityManagerInterface::class);
+
+        $userGroup = $entityManager->createQuery('SELECT ug FROM '.UserGroup::class.' ug ')
+            ->setMaxResults(1)->getOneOrNullResult();
+
+        if (null === $userGroup) {
+            throw new \RuntimeException('User group not existing in database');
+        }
+
+        $user = $entityManager->createQuery('SELECT u FROM '.User::class.' u')
+            ->setMaxResults(1)->getOneOrNullResult();
+
+        if (null === $user) {
+            throw new \RuntimeException('User not existing in database');
+        }
+
+        self::ensureKernelShutdown();
+
+        yield [['type' => 'user', 'id' => $user->getId()]];
+        yield [['type' => 'user_group', 'id' => $userGroup->getId()]];
+    }
+
+    public static function getContentData(): iterable
+    {
+        self::bootKernel();
+        $entityManager = self::getContainer()->get(EntityManagerInterface::class);
+
+        $userGroup = $entityManager->createQuery('SELECT ug FROM '.UserGroup::class.' ug ')
+            ->setMaxResults(1)->getOneOrNullResult();
+
+        if (null === $userGroup) {
+            throw new \RuntimeException('User group not existing in database');
+        }
+
+        $user = $entityManager->createQuery('SELECT u FROM '.User::class.' u')
+            ->setMaxResults(1)->getOneOrNullResult();
+
+        if (null === $user) {
+            throw new \RuntimeException('User not existing in database');
+        }
+
+        self::ensureKernelShutdown();
+
+        yield [[['type' => 'user', 'id' => $user->getId()]]];
+        yield [[['type' => 'user', 'id' => $user->getId()], ['type' => 'user_group', 'id' => $userGroup->getId()]]];
+        yield [[['type' => 'user_group', 'id' => $userGroup->getId()]]];
+    }
+
+    private function buildController(bool $willSave, bool $isValid): SetAddresseesController
+    {
+        $user = new User();
+        $security = $this->prophesize(Security::class);
+        $security->isGranted('ROLE_USER')->willReturn(true);
+        $security->getUser()->willReturn($user);
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+
+        if ($willSave) {
+            $entityManager->flush()->shouldBeCalled();
+            $entityManager->persist(Argument::type(AddresseeHistory::class))->shouldBeCalled();
+        }
+
+        $validator = $this->prophesize(ValidatorInterface::class);
+
+        if ($isValid) {
+            $validator->validate(Argument::type(SetAddresseesCommand::class))->willReturn(new ConstraintViolationList([]));
+        } else {
+            $validator->validate(Argument::type(SetAddresseesCommand::class))->willReturn(
+                new ConstraintViolationList([
+                    new ConstraintViolation('Fake constraint', 'fake message template', [], [], 'addresses', []),
+                ])
+            );
+        }
+
+        return new SetAddresseesController(
+            $security->reveal(),
+            $entityManager->reveal(),
+            $this->serializer,
+            new SetAddresseesCommandHandler(new MockClock(), $entityManager->reveal(), $security->reveal()),
+            $validator->reveal()
+        );
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/tests/Entity/TicketTest.php b/src/Bundle/ChillTicketBundle/tests/Entity/TicketTest.php
index 6f710f1aa..f0efe5493 100644
--- a/src/Bundle/ChillTicketBundle/tests/Entity/TicketTest.php
+++ b/src/Bundle/ChillTicketBundle/tests/Entity/TicketTest.php
@@ -11,7 +11,10 @@ declare(strict_types=1);
 
 namespace Chill\TicketBundle\Tests\Entity;
 
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
 use Chill\PersonBundle\Entity\Person;
+use Chill\TicketBundle\Entity\AddresseeHistory;
 use Chill\TicketBundle\Entity\Motive;
 use Chill\TicketBundle\Entity\MotiveHistory;
 use Chill\TicketBundle\Entity\PersonHistory;
@@ -57,5 +60,33 @@ class TicketTest extends KernelTestCase
 
         self::assertCount(1, $ticket->getPersons());
         self::assertSame($person, $ticket->getPersons()[0]);
+
+        $history->setEndDate(new \DateTimeImmutable('now'));
+
+        self::assertCount(0, $ticket->getPersons());
+    }
+
+    public function testGetAddresse(): void
+    {
+        $ticket = new Ticket();
+        $user = new User();
+        $group = new UserGroup();
+
+        self::assertEquals([], $ticket->getCurrentAddressee());
+
+        $history = new AddresseeHistory($user, new \DateTimeImmutable('now'), $ticket);
+
+        self::assertCount(1, $ticket->getCurrentAddressee());
+        self::assertSame($user, $ticket->getCurrentAddressee()[0]);
+
+        $history2 = new AddresseeHistory($group, new \DateTimeImmutable('now'), $ticket);
+
+        self::assertCount(2, $ticket->getCurrentAddressee());
+        self::assertContains($group, $ticket->getCurrentAddressee());
+
+        $history->setEndDate(new \DateTimeImmutable('now'));
+
+        self::assertCount(1, $ticket->getCurrentAddressee());
+        self::assertSame($group, $ticket->getCurrentAddressee()[0]);
     }
 }
diff --git a/src/Bundle/ChillTicketBundle/tests/Serializer/Normalizer/SetAddresseesCommandDenormalizerTest.php b/src/Bundle/ChillTicketBundle/tests/Serializer/Normalizer/SetAddresseesCommandDenormalizerTest.php
new file mode 100644
index 000000000..a4b9bbf49
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/tests/Serializer/Normalizer/SetAddresseesCommandDenormalizerTest.php
@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\TicketBundle\Tests\Serializer\Normalizer;
+
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
+use Chill\TicketBundle\Action\Ticket\SetAddresseesCommand;
+use Chill\TicketBundle\Serializer\Normalizer\SetAddresseesCommandDenormalizer;
+use PHPUnit\Framework\TestCase;
+use Prophecy\Argument;
+use Prophecy\PhpUnit\ProphecyTrait;
+use Symfony\Component\Serializer\Normalizer\DenormalizerInterface;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+class SetAddresseesCommandDenormalizerTest extends TestCase
+{
+    use ProphecyTrait;
+
+    public function testSupportsDenormalization()
+    {
+        $denormalizer = new SetAddresseesCommandDenormalizer();
+
+        self::assertTrue($denormalizer->supportsDenormalization('', SetAddresseesCommand::class, 'json'));
+        self::assertFalse($denormalizer->supportsDenormalization('', stdClass::class, 'json'));
+    }
+
+    public function testDenormalize()
+    {
+        $denormalizer = $this->buildDenormalizer();
+
+        $actual = $denormalizer->denormalize(['addressees' => [['type' => 'user'], ['type' => 'user_group']]], SetAddresseesCommand::class, 'json');
+
+        self::assertInstanceOf(SetAddresseesCommand::class, $actual);
+        self::assertIsArray($actual->addressees);
+        self::assertCount(2, $actual->addressees);
+        self::assertInstanceOf(User::class, $actual->addressees[0]);
+        self::assertInstanceOf(UserGroup::class, $actual->addressees[1]);
+    }
+
+    private function buildDenormalizer(): SetAddresseesCommandDenormalizer
+    {
+        $normalizer = $this->prophesize(DenormalizerInterface::class);
+        $normalizer->denormalize(Argument::any(), User::class, 'json', Argument::any())
+            ->willReturn(new User());
+        $normalizer->denormalize(Argument::any(), UserGroup::class, 'json', Argument::any())
+            ->willReturn(new UserGroup());
+
+        $denormalizer = new SetAddresseesCommandDenormalizer();
+        $denormalizer->setDenormalizer($normalizer->reveal());
+
+        return $denormalizer;
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/tests/Serializer/Normalizer/TicketNormalizerTest.php b/src/Bundle/ChillTicketBundle/tests/Serializer/Normalizer/TicketNormalizerTest.php
index e876341cd..415fc15fb 100644
--- a/src/Bundle/ChillTicketBundle/tests/Serializer/Normalizer/TicketNormalizerTest.php
+++ b/src/Bundle/ChillTicketBundle/tests/Serializer/Normalizer/TicketNormalizerTest.php
@@ -11,7 +11,11 @@ declare(strict_types=1);
 
 namespace Chill\TicketBundle\Tests\Serializer\Normalizer;
 
+use Chill\MainBundle\Entity\User;
+use Chill\MainBundle\Entity\UserGroup;
 use Chill\PersonBundle\Entity\Person;
+use Chill\TicketBundle\Entity\AddresseeHistory;
+use Chill\TicketBundle\Entity\Comment;
 use Chill\TicketBundle\Entity\Motive;
 use Chill\TicketBundle\Entity\MotiveHistory;
 use Chill\TicketBundle\Entity\PersonHistory;
@@ -93,11 +97,22 @@ class TicketNormalizerTest extends KernelTestCase
         // datetime
         $normalizer->normalize(Argument::type(\DateTimeImmutable::class), 'json', Argument::type('array'))
             ->will(function ($args) { return $args[0]->getTimestamp(); });
+        // user
+        $normalizer->normalize(Argument::type(User::class), 'json', Argument::type('array'))
+            ->willReturn(['user']);
+        // motive
         $normalizer->normalize(Argument::type(Motive::class), 'json', Argument::type('array'))->willReturn(['type' => 'motive', 'id' => 0]);
+        // person history
         $normalizer->normalize(Argument::type(PersonHistory::class), 'json', Argument::type('array'))
             ->willReturn(['personHistory']);
+        // motive history
         $normalizer->normalize(Argument::type(MotiveHistory::class), 'json', Argument::type('array'))
             ->willReturn(['motiveHistory']);
+        $normalizer->normalize(Argument::type(Comment::class), 'json', Argument::type('array'))
+            ->willReturn(['comment']);
+        $normalizer->normalize(Argument::type(AddresseeHistory::class), 'json', Argument::type('array'))
+            ->willReturn(['addresseeHistory']);
+        // null values
         $normalizer->normalize(null, 'json', Argument::type('array'))->willReturn(null);
 
         $ticketNormalizer = new TicketNormalizer();
@@ -109,6 +124,7 @@ class TicketNormalizerTest extends KernelTestCase
     public static function provideTickets(): iterable
     {
         yield [
+            // this a nearly empty ticket
             new Ticket(),
             [
                 'type' => 'ticket_ticket',
@@ -122,10 +138,17 @@ class TicketNormalizerTest extends KernelTestCase
             ],
         ];
 
+        // ticket with more features
         $ticket = new Ticket();
         $ticket->setExternalRef('2134');
         $personHistory = new PersonHistory(new Person(), $ticket, new \DateTimeImmutable('2024-04-01T12:00:00'));
         $ticketHistory = new MotiveHistory(new Motive(), $ticket, new \DateTimeImmutable('2024-04-01T12:02:00'));
+        $comment = new Comment('blabla test', $ticket);
+        $comment->setCreatedAt(new \DateTimeImmutable('2024-04-01T12:04:00'));
+        $comment->setCreatedBy(new User());
+        $addresseeHistory = new AddresseeHistory(new User(), new \DateTimeImmutable('2024-04-01T12:05:00'), $ticket);
+        $addresseeHistory->setEndDate(new \DateTimeImmutable('2024-04-01T12:06:00'));
+        new AddresseeHistory(new UserGroup(), new \DateTimeImmutable('2024-04-01T12:07:00'), $ticket);
 
         yield [
             $ticket,
@@ -134,10 +157,17 @@ class TicketNormalizerTest extends KernelTestCase
                 'id' => null,
                 'externalRef' => '2134',
                 'currentPersons' => ['embedded'],
-                'currentAddressees' => [],
+                'currentAddressees' => ['embedded'],
                 'currentInputs' => [],
                 'currentMotive' => ['type' => 'motive', 'id' => 0],
-                'history' => [['event_type' => 'add_person'], ['event_type' => 'set_motive']],
+                'history' => [
+                    ['event_type' => 'add_person'],
+                    ['event_type' => 'set_motive'],
+                    ['event_type' => 'add_comment'],
+                    ['event_type' => 'add_addressee'],
+                    ['event_type' => 'remove_addressee'],
+                    ['event_type' => 'add_addressee'],
+                ],
             ],
         ];
     }