diff --git a/src/Bundle/ChillTicketBundle/chill.api.specs.yaml b/src/Bundle/ChillTicketBundle/chill.api.specs.yaml
index e15b57ba5..ce53732ff 100644
--- a/src/Bundle/ChillTicketBundle/chill.api.specs.yaml
+++ b/src/Bundle/ChillTicketBundle/chill.api.specs.yaml
@@ -13,6 +13,18 @@ components:
                         fr: Retard de livraison
                 active:
                     type: boolean
+        MotiveById:
+            type: object
+            properties:
+                id:
+                    type: integer
+                type:
+                    type: string
+                    enum:
+                        - ticket_motive
+            required:
+                - id
+                - type
 
 paths:
     /1.0/ticket/motive.json:
@@ -23,3 +35,32 @@ paths:
             responses:
                 200:
                     description: "OK"
+
+    /1.0/ticket/{id}/motive/set:
+        post:
+            tags:
+                - ticket
+            summary: Replace the existing ticket's motive by a new one
+            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:
+                                motive:
+                                    $ref: "#/components/schemas/MotiveById"
+            responses:
+                201:
+                    description: "ACCEPTED"
+                422:
+                    description: "UNPROCESSABLE ENTITY"
diff --git a/src/Bundle/ChillTicketBundle/src/Action/Ticket/Handler/ReplaceMotiveCommandHandler.php b/src/Bundle/ChillTicketBundle/src/Action/Ticket/Handler/ReplaceMotiveCommandHandler.php
new file mode 100644
index 000000000..7363d5e73
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Action/Ticket/Handler/ReplaceMotiveCommandHandler.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\TicketBundle\Action\Ticket\ReplaceMotiveCommand;
+use Chill\TicketBundle\Entity\MotiveHistory;
+use Chill\TicketBundle\Entity\Ticket;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Component\Clock\ClockInterface;
+
+final readonly class ReplaceMotiveCommandHandler
+{
+    public function __construct(
+        private ClockInterface $clock,
+        private EntityManagerInterface $entityManager,
+    ) {}
+
+    public function handle(Ticket $ticket, ReplaceMotiveCommand $command): void
+    {
+        if (null === $command->motive) {
+            throw new \InvalidArgumentException('The new motive cannot be null');
+        }
+
+        // will add if there are no existing motive
+        $readyToAdd = 0 === count($ticket->getMotiveHistories());
+
+        foreach ($ticket->getMotiveHistories() as $history) {
+            if (null !== $history->getEndDate()) {
+                continue;
+            }
+
+            if ($history->getMotive() === $command->motive) {
+                // we apply the same motive, we do nothing
+                continue;
+            }
+
+            $history->setEndDate($this->clock->now());
+            $readyToAdd = true;
+        }
+
+        if ($readyToAdd) {
+            $history = new MotiveHistory($command->motive, $ticket, $this->clock->now());
+            $ticket->addMotiveHistory($history);
+            $this->entityManager->persist($history);
+        }
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Action/Ticket/ReplaceMotiveCommand.php b/src/Bundle/ChillTicketBundle/src/Action/Ticket/ReplaceMotiveCommand.php
new file mode 100644
index 000000000..75e2a3f1b
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Action/Ticket/ReplaceMotiveCommand.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 Chill\TicketBundle\Entity\Motive;
+use Symfony\Component\Serializer\Annotation\Groups;
+use Symfony\Component\Validator\Constraints as Assert;
+
+final readonly class ReplaceMotiveCommand
+{
+    public function __construct(
+        #[Assert\NotNull]
+        #[Groups(['write'])]
+        public ?Motive $motive,
+    ) {}
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Controller/ReplaceMotiveController.php b/src/Bundle/ChillTicketBundle/src/Controller/ReplaceMotiveController.php
new file mode 100644
index 000000000..d6f1acf94
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/src/Controller/ReplaceMotiveController.php
@@ -0,0 +1,64 @@
+<?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\Handler\ReplaceMotiveCommandHandler;
+use Chill\TicketBundle\Action\Ticket\ReplaceMotiveCommand;
+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 ReplaceMotiveController
+{
+    public function __construct(
+        private Security $security,
+        private ReplaceMotiveCommandHandler $replaceMotiveCommandHandler,
+        private SerializerInterface $serializer,
+        private ValidatorInterface $validator,
+        private EntityManagerInterface $entityManager,
+    ) {}
+
+    #[Route('/api/1.0/ticket/{id}/motive/set', name: 'chill_ticket_motive_set', methods: ['POST'])]
+    public function __invoke(Ticket $ticket, Request $request): Response
+    {
+        if (!$this->security->isGranted('ROLE_USER')) {
+            throw new AccessDeniedHttpException('');
+        }
+
+        $command = $this->serializer->deserialize($request->getContent(), ReplaceMotiveCommand::class, 'json', [
+            AbstractNormalizer::GROUPS => ['write'],
+        ]);
+
+        $errors = $this->validator->validate($command);
+
+        if (0 < $errors->count()) {
+            return new JsonResponse(
+                $this->serializer->serialize($errors, 'json'),
+                Response::HTTP_UNPROCESSABLE_ENTITY,
+            );
+        }
+
+        $this->replaceMotiveCommandHandler->handle($ticket, $command);
+
+        $this->entityManager->flush();
+
+        return new JsonResponse(null, Response::HTTP_CREATED);
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/src/Entity/Ticket.php b/src/Bundle/ChillTicketBundle/src/Entity/Ticket.php
index f74a55a3f..3551aa93d 100644
--- a/src/Bundle/ChillTicketBundle/src/Entity/Ticket.php
+++ b/src/Bundle/ChillTicketBundle/src/Entity/Ticket.php
@@ -114,6 +114,11 @@ class Ticket implements TrackCreationInterface, TrackUpdateInterface
         $this->personHistories->add($personHistory);
     }
 
+    public function addMotiveHistory(MotiveHistory $motiveHistory): void
+    {
+        $this->motiveHistories->add($motiveHistory);
+    }
+
     /**
      * @return list<UserGroup|User>
      */
@@ -163,4 +168,12 @@ class Ticket implements TrackCreationInterface, TrackUpdateInterface
 
         return null;
     }
+
+    /**
+     * @return ReadableCollection<int, MotiveHistory>
+     */
+    public function getMotiveHistories(): ReadableCollection
+    {
+        return $this->motiveHistories;
+    }
 }
diff --git a/src/Bundle/ChillTicketBundle/tests/Action/Ticket/Handler/ReplaceMotiveCommandHandlerTest.php b/src/Bundle/ChillTicketBundle/tests/Action/Ticket/Handler/ReplaceMotiveCommandHandlerTest.php
new file mode 100644
index 000000000..ef86dad17
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/tests/Action/Ticket/Handler/ReplaceMotiveCommandHandlerTest.php
@@ -0,0 +1,108 @@
+<?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\Handler\ReplaceMotiveCommandHandler;
+use Chill\TicketBundle\Action\Ticket\ReplaceMotiveCommand;
+use Chill\TicketBundle\Entity\Motive;
+use Chill\TicketBundle\Entity\MotiveHistory;
+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;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+final class ReplaceMotiveCommandHandlerTest extends KernelTestCase
+{
+    use ProphecyTrait;
+
+    private function buildHandler(
+        EntityManagerInterface $entityManager,
+    ): ReplaceMotiveCommandHandler {
+        $clock = new MockClock();
+
+        return new ReplaceMotiveCommandHandler($clock, $entityManager);
+    }
+
+    public function testHandleOnTicketWithoutMotive(): void
+    {
+        $motive = new Motive();
+        $ticket = new Ticket();
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+        $entityManager->persist(Argument::that(static function ($arg) use ($motive): bool {
+            if (!$arg instanceof MotiveHistory) {
+                return false;
+            }
+
+            return $arg->getMotive() === $motive;
+        }))->shouldBeCalled();
+
+        $handler = $this->buildHandler($entityManager->reveal());
+
+        $handler->handle($ticket, new ReplaceMotiveCommand($motive));
+
+        self::assertSame($motive, $ticket->getMotive());
+    }
+
+    public function testHandleReplaceMotiveOnTicketWithExistingMotive(): void
+    {
+        $motive = new Motive();
+        $ticket = new Ticket();
+        $ticket->addMotiveHistory(new MotiveHistory(new Motive(), $ticket));
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+        $entityManager->persist(Argument::that(static function ($arg) use ($motive): bool {
+            if (!$arg instanceof MotiveHistory) {
+                return false;
+            }
+
+            return $arg->getMotive() === $motive;
+        }))->shouldBeCalled();
+
+        $handler = $this->buildHandler($entityManager->reveal());
+
+        $handler->handle($ticket, new ReplaceMotiveCommand($motive));
+
+        self::assertSame($motive, $ticket->getMotive());
+        self::assertCount(2, $ticket->getMotiveHistories());
+    }
+
+    public function testHandleReplaceMotiveOnTicketWithSameMotive(): void
+    {
+        $motive = new Motive();
+        $ticket = new Ticket();
+        $ticket->addMotiveHistory(new MotiveHistory($motive, $ticket));
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+        $entityManager->persist(Argument::that(static function ($arg) use ($motive): bool {
+            if (!$arg instanceof MotiveHistory) {
+                return false;
+            }
+
+            return $arg->getMotive() === $motive;
+        }))->shouldNotBeCalled();
+
+        $handler = $this->buildHandler($entityManager->reveal());
+
+        $handler->handle($ticket, new ReplaceMotiveCommand($motive));
+
+        self::assertSame($motive, $ticket->getMotive());
+        self::assertCount(1, $ticket->getMotiveHistories());
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/tests/Controller/ReplaceMotiveControllerTest.php b/src/Bundle/ChillTicketBundle/tests/Controller/ReplaceMotiveControllerTest.php
new file mode 100644
index 000000000..dcf6a2318
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/tests/Controller/ReplaceMotiveControllerTest.php
@@ -0,0 +1,113 @@
+<?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\ReplaceMotiveCommandHandler;
+use Chill\TicketBundle\Controller\ReplaceMotiveController;
+use Chill\TicketBundle\Entity\Motive;
+use Chill\TicketBundle\Entity\MotiveHistory;
+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\Validator\ValidatorInterface;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+class ReplaceMotiveControllerTest extends KernelTestCase
+{
+    use ProphecyTrait;
+
+    private SerializerInterface $serializer;
+
+    private ValidatorInterface $validator;
+
+    protected function setUp(): void
+    {
+        self::bootKernel();
+        $this->serializer = self::getContainer()->get(SerializerInterface::class);
+        $this->validator = self::getContainer()->get(ValidatorInterface::class);
+    }
+
+    protected function tearDown(): void
+    {
+        self::ensureKernelShutdown();
+    }
+
+    /**
+     * @dataProvider generateMotiveId
+     */
+    public function testAddValidMotive(int $motiveId): void
+    {
+        $ticket = new Ticket();
+        $payload = <<<JSON
+            {"motive": {"type":  "ticket_motive", "id":  {$motiveId}}}
+            JSON;
+
+        $request = new Request(content: $payload);
+
+        $controller = $this->buildController();
+
+        $response = $controller($ticket, $request);
+
+        self::assertEquals(201, $response->getStatusCode());
+    }
+
+    private function buildController(): ReplaceMotiveController
+    {
+        $security = $this->prophesize(Security::class);
+        $security->isGranted('ROLE_USER')->willReturn(true);
+
+        $entityManager = $this->prophesize(EntityManagerInterface::class);
+        $entityManager->persist(Argument::type(MotiveHistory::class))->shouldBeCalled();
+        $entityManager->flush()->shouldBeCalled();
+
+        $handler = new ReplaceMotiveCommandHandler(
+            new MockClock(),
+            $entityManager->reveal()
+        );
+
+        return new ReplaceMotiveController(
+            $security->reveal(),
+            $handler,
+            $this->serializer,
+            $this->validator,
+            $entityManager->reveal(),
+        );
+    }
+
+    public static function generateMotiveId(): iterable
+    {
+        self::bootKernel();
+        $em = self::getContainer()->get(EntityManagerInterface::class);
+
+        $motive = $em->createQuery('SELECT m FROM '.Motive::class.' m ')
+            ->setMaxResults(1)
+            ->getOneOrNullResult();
+
+        if (null === $motive) {
+            throw new \RuntimeException('the motive table seems to be empty');
+        }
+
+        self::ensureKernelShutdown();
+
+        yield [$motive->getId()];
+    }
+}
diff --git a/src/Bundle/ChillTicketBundle/tests/Entity/TicketTest.php b/src/Bundle/ChillTicketBundle/tests/Entity/TicketTest.php
new file mode 100644
index 000000000..f8d7ad270
--- /dev/null
+++ b/src/Bundle/ChillTicketBundle/tests/Entity/TicketTest.php
@@ -0,0 +1,47 @@
+<?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\Entity;
+
+use Chill\TicketBundle\Entity\Motive;
+use Chill\TicketBundle\Entity\MotiveHistory;
+use Chill\TicketBundle\Entity\Ticket;
+use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
+
+/**
+ * @internal
+ *
+ * @coversNothing
+ */
+class TicketTest extends KernelTestCase
+{
+    public function testGetMotive(): void
+    {
+        $ticket = new Ticket();
+        $motive = new Motive();
+
+        self::assertNull($ticket->getMotive());
+
+        $history = new MotiveHistory($motive, $ticket);
+        $ticket->addMotiveHistory($history);
+
+        self::assertSame($motive, $ticket->getMotive());
+        self::assertCount(1, $ticket->getMotiveHistories());
+
+        // replace motive
+        $motive2 = new Motive();
+        $history->setEndDate(new \DateTimeImmutable());
+        $ticket->addMotiveHistory(new MotiveHistory($motive2, $ticket));
+
+        self::assertCount(2, $ticket->getMotiveHistories());
+        self::assertSame($motive2, $ticket->getMotive());
+    }
+}