diff --git a/src/Bundle/ChillPersonBundle/Controller/AccompanyingPeriodController.php b/src/Bundle/ChillPersonBundle/Controller/AccompanyingPeriodController.php
index 6b6e4dda9..2b51e9191 100644
--- a/src/Bundle/ChillPersonBundle/Controller/AccompanyingPeriodController.php
+++ b/src/Bundle/ChillPersonBundle/Controller/AccompanyingPeriodController.php
@@ -88,12 +88,12 @@ class AccompanyingPeriodController extends AbstractController
         $this->denyAccessUnlessGranted(PersonVoter::UPDATE, $person,
                 'You are not allowed to update this person');
 
-        $accompanyingPeriod = new AccompanyingPeriod(new \DateTime());
-        $accompanyingPeriod->setClosingDate(new \DateTime());
-
-        $person->addAccompanyingPeriod(
-            $accompanyingPeriod);
-
+        $accompanyingPeriod = new AccompanyingPeriod(new \DateTimeImmutable('now'));
+        $accompanyingPeriod->setClosingDate(new \DateTimeImmutable('now'));
+        
+        $accompanyingPeriod->addPerson($person);
+        //or $person->addAccompanyingPeriod($accompanyingPeriod);
+        
         $form = $this->createForm(
             AccompanyingPeriodType::class,
             $accompanyingPeriod, [
@@ -153,8 +153,9 @@ class AccompanyingPeriodController extends AbstractController
         }
 
         /** @var Person $person */
-        $person = $em->getRepository(Person::class)->find($person_id);
+        $person = $this->_getPerson($person_id);
         
+        // CHECK
         if (! $accompanyingPeriod->containsPerson($person)) {
             throw new Exception("Accompanying period " . $period_id . " does not contain person " . $person_id);
         }
diff --git a/src/Bundle/ChillPersonBundle/Entity/AccompanyingPeriod.php b/src/Bundle/ChillPersonBundle/Entity/AccompanyingPeriod.php
index 29355b5b8..915500392 100644
--- a/src/Bundle/ChillPersonBundle/Entity/AccompanyingPeriod.php
+++ b/src/Bundle/ChillPersonBundle/Entity/AccompanyingPeriod.php
@@ -35,7 +35,7 @@ use Chill\MainBundle\Entity\User;
 /**
  * AccompanyingPeriod Class
  *
- * @ORM\Entity(repositoryClass=AccompanyingPeriodRepository::class)
+ * @ORM\Entity(repositoryClass="Chill\PersonBundle\Repository\AccompanyingPeriodRepository")
  * @ORM\Table(name="chill_person_accompanying_period")
  */
 class AccompanyingPeriod
@@ -79,9 +79,10 @@ class AccompanyingPeriod
      * @var Collection
      *
      * @ORM\OneToMany(targetEntity=AccompanyingPeriodParticipation::class,
-     *     mappedBy="accompanyingPeriod")
+     *     mappedBy="accompanyingPeriod",
+     *     cascade={"persist", "remove", "merge", "detach"})
      */
-    private $persons;
+    private $participations;
     
     /**
      * @var AccompanyingPeriod\ClosingMotive
@@ -175,7 +176,7 @@ class AccompanyingPeriod
      */
     public function __construct(\DateTime $dateOpening) {
         $this->setOpeningDate($dateOpening);
-        $this->persons = new ArrayCollection();
+        $this->participations = new ArrayCollection();
         $this->scopes = new ArrayCollection();
     }
 
@@ -280,37 +281,63 @@ class AccompanyingPeriod
     {
         return $this->remark;
     }
-
-    public function getPersons(): Collection
-    {
-        return $this->persons;
-    }
     
-    public function containsPerson(Person $person): bool
+    /**
+     * Get Participations Collection
+     */
+    public function getParticipations(): Collection
     {
-        foreach ($this->persons as $p) {
-            if ($p === $person) { return true; }
-        }
-
-        return false;
+        return $this->participations;
     }
     
     /**
-     * For consistency, you should use Person::addAccompanyingPeriod instead.
-     * @see Person::addAccompanyingPeriod
+     * This private function scan Participations Collection,
+     * searching for a given Person
+     */
+    private function participationsContainsPerson(Person $person): ?AccompanyingPeriodParticipation
+    {
+        foreach ($this->participations as $participation) {
+            /** @var AccompanyingPeriodParticipation $participation */
+            if ($person === $participation->getPerson()) {
+                return $participation;
+        }}
+
+        return null;
+    }
+    
+    /**
+     * This public function is the same but return only true or false
+     */
+    public function containsPerson(Person $person): bool
+    {
+        return ($this->participationsContainsPerson($person) === null) ? false : true;
+    }
+    
+    /**
+     * Add Person
      */
     public function addPerson(Person $person = null): self
     {
-        $this->persons[] = $person;
+        $participation = new AccompanyingPeriodParticipation($this, $person);
+        $this->participations[] = $participation;
     
         return $this;
     }
     
+    /**
+     * Remove Person
+     */
     public function removePerson(Person $person): void
     {
-        $this->persons->removeElement($person);
+        $participation = $this->participationsContainsPerson($person);
+        
+        if (! null === $participation) {
+            $participation->setEndDate(new \DateTimeImmutable('now'));
+            $this->participations->removeElement($participation);
+        }
     }
     
+    
     public function getClosingMotive(): ?ClosingMotive
     {
         return $this->closingMotive;
@@ -335,11 +362,12 @@ class AccompanyingPeriod
             return false;
         }
         
-        foreach ($this->getPersons() as $p) {
-            if ($p === $person) {
-                $periods = $p->getAccompanyingPeriodsOrdered();
-                return end($periods) === $this;
-            }
+        $participation = $this->participationsContainsPerson($person);
+        if (!null === $participation)
+        {
+            $person = $participation->getPerson();
+            $periods = $person->getAccompanyingPeriodsOrdered();
+            return end($periods) === $this;
         }
         
         return false;
diff --git a/src/Bundle/ChillPersonBundle/Entity/AccompanyingPeriodParticipation.php b/src/Bundle/ChillPersonBundle/Entity/AccompanyingPeriodParticipation.php
index 4a2fe3b44..9a807b179 100644
--- a/src/Bundle/ChillPersonBundle/Entity/AccompanyingPeriodParticipation.php
+++ b/src/Bundle/ChillPersonBundle/Entity/AccompanyingPeriodParticipation.php
@@ -44,22 +44,81 @@ class AccompanyingPeriodParticipation
     private $id;
     
     /**
-     * @ORM\ManyToOne(targetEntity=Person::class,
-     *     inversedBy="accompanyingPeriods")
+     * @ORM\ManyToOne(targetEntity=Person::class, inversedBy="accompanyingPeriodParticipations")
      * @ORM\JoinColumn(name="person_id", referencedColumnName="id", nullable=false)
      */
     private $person;
     
     /**
-     * @ORM\ManyToOne(targetEntity=AccompanyingPeriod::class,
-     *     inversedBy="persons")
+     * @ORM\ManyToOne(targetEntity=AccompanyingPeriod::class, inversedBy="participations")
      * @ORM\JoinColumn(name="accompanyingperiod_id", referencedColumnName="id", nullable=false)
      */
     private $accompanyingPeriod;
     
+    /**
+     * @ORM\Column(type="date", nullable=false)
+     */
+    private $startDate;
+    
+    /**
+     * @ORM\Column(type="date", nullable=true)
+     */
+    private $endDate = null;
+    
+    public function __construct(AccompanyingPeriod $accompanyingPeriod, Person $person)
+    {
+        $this->startDate = new \DateTimeImmutable('now');
+        $this->accompanyingPeriod = $accompanyingPeriod;
+        $this->person = $person;
+    }
     
     public function getId(): ?int
     {
         return $this->id;
     }
+    
+    public function getPerson(): ?Person
+    {
+        return $this->person;
+    }
+    
+    public function setPerson(?Person $person): self
+    {
+        $this->person = $person;
+        
+        return $this;
+    }
+    
+    public function getAccompanyingPeriod(): ?AccompanyingPeriod
+    {
+        return $this->accompanyingPeriod;
+    }
+    
+    public function setAccompanyingPeriod(?AccompanyingPeriod $accompanyingPeriod): self
+    {
+        $this->accompanyingPeriod = $accompanyingPeriod;
+        
+        return $this;
+    }
+    
+    public function getStartDate(): ?\DateTimeInterface
+    {
+        return $this->startDate;
+    }
+    
+    /*
+     * public function setStartDate(\DateTimeInterface $startDate): self { $this->startDate = $startDate; return $this; }
+     */
+    
+    public function getEndDate(): ?\DateTimeInterface
+    {
+        return $this->endDate;
+    }
+    
+    public function setEndDate(?\DateTimeInterface $endDate): self
+    {
+        $this->endDate = $endDate;
+        
+        return $this;
+    }
 }
diff --git a/src/Bundle/ChillPersonBundle/Entity/Person.php b/src/Bundle/ChillPersonBundle/Entity/Person.php
index bd89fbcea..e3a01a055 100644
--- a/src/Bundle/ChillPersonBundle/Entity/Person.php
+++ b/src/Bundle/ChillPersonBundle/Entity/Person.php
@@ -209,7 +209,7 @@ class Person implements HasCenterInterface
      *     mappedBy="person",
      *     cascade={"persist", "remove", "merge", "detach"})
      */
-    private $accompanyingPeriods;
+    private $accompanyingPeriodParticipations;
 
     /**
      * A remark over the person
@@ -262,7 +262,7 @@ class Person implements HasCenterInterface
      */
     public function __construct(\DateTime $opening = null)
     {
-        $this->accompanyingPeriods = new ArrayCollection();
+        $this->accompanyingPeriodParticipations = new ArrayCollection();
         $this->spokenLanguages = new ArrayCollection();
         $this->addresses = new ArrayCollection();
         $this->altNames = new ArrayCollection();
@@ -273,16 +273,39 @@ class Person implements HasCenterInterface
 
         $this->open(new AccompanyingPeriod($opening));
     }
-
+    
     /**
-     * Add AccompanyingPeriod
+     * This private function scan accompanyingPeriodParticipations Collection,
+     * searching for a given AccompanyingPeriod
+     */
+    private function participationsContainAccompanyingPeriod(AccompanyingPeriod $accompanyingPeriod): ?AccompanyingPeriodParticipation
+    {
+        foreach ($this->accompanyingPeriodParticipations as $participation) {
+            /** @var AccompanyingPeriodParticipation $participation */
+            if ($accompanyingPeriod === $participation->getAccompanyingPeriod()) {
+                return $participation;
+        }}
+        
+        return null;
+    }
+    
+    /**
+     * This public function is the same but return only true or false
+     */
+    public function containsAccompanyingPeriod(AccompanyingPeriod $accompanyingPeriod): bool
+    {
+        return ($this->participationsContainAccompanyingPeriod($accompanyingPeriod)) ? false : true;
+    }
+    
+    /**
+     * Add AccompanyingPeriodParticipation
      *
      * @uses AccompanyingPeriod::addPerson
      */
     public function addAccompanyingPeriod(AccompanyingPeriod $accompanyingPeriod): self
     {
-        $accompanyingPeriod->addPerson($this);
-        $this->accompanyingPeriods->add($accompanyingPeriod);
+        $participation = new AccompanyingPeriodParticipation($accompanyingPeriod, $this);
+        $this->accompanyingPeriodParticipations->add($participation);
         
         return $this;
     }
@@ -292,7 +315,12 @@ class Person implements HasCenterInterface
      */
     public function removeAccompanyingPeriod(AccompanyingPeriod $accompanyingPeriod) : void
     {
-        $this->accompanyingPeriods->remove($accompanyingPeriod);
+        $participation = $this->participationsContainAccompanyingPeriod($accompanyingPeriod);
+        
+        if (! null === $participation) {
+            $participation->setEndDate(\DateTimeImmutable::class);
+            $this->accompanyingPeriodParticipations->removeElement($participation);
+        }
     }
 
     /**
@@ -335,9 +363,10 @@ class Person implements HasCenterInterface
             return null;
         }
 
-        foreach ($this->accompanyingPeriods as $period) {
-            if ($period->isOpen()) {
-                return $period;
+        foreach ($this->accompanyingPeriodParticipations as $participation) {
+            /** @var AccompanyingPeriodParticipation $participation */
+            if ($participation->getAccompanyingPeriod()->isOpen()) {
+                return $participation->getAccompanyingPeriod();
             }
         }
     }
@@ -353,19 +382,33 @@ class Person implements HasCenterInterface
     }
 
     /**
-     * Get AccompanyingPeriods Collection
+     * Get AccompanyingPeriods array
      */
-    public function getAccompanyingPeriods() : Collection
+    public function getAccompanyingPeriods(): array
     {
-        return $this->accompanyingPeriods;
+        $accompanyingPeriods = [];
+        foreach ($this->accompanyingPeriodParticipations as $participation)
+        {
+            /** @var AccompanyingPeriodParticipation $participation */
+            $accompanyingPeriods[] = $participation->getAccompanyingPeriod();
+        }
+        return $accompanyingPeriods;
+    }
+    
+    /**
+     * Get AccompanyingPeriodParticipations Collection
+     */
+    public function getAccompanyingPeriodParticipations(): Collection
+    {
+        return $this->accompanyingPeriodParticipations;
     }
 
     /**
      * Get the accompanying periods of a give person with the chronological order.
      */
-    public function getAccompanyingPeriodsOrdered() : array
+    public function getAccompanyingPeriodsOrdered(): array
     {
-        $periods = $this->getAccompanyingPeriods()->toArray();
+        $periods = $this->getAccompanyingPeriods();
 
         //order by date :
         usort($periods, function($a, $b) {
@@ -504,7 +547,7 @@ class Person implements HasCenterInterface
      * @param PersonAltName $altName
      * @return $this
      */
-    public function removeAltName(PersonAltName $altName) 
+    public function removeAltName(PersonAltName $altName)
     {
         if ($this->altNames->contains($altName)) {
             $altName->setPerson(null);
diff --git a/src/Bundle/ChillPersonBundle/config/services/repository.yaml b/src/Bundle/ChillPersonBundle/config/services/repository.yaml
index 50209b010..8cfaa8471 100644
--- a/src/Bundle/ChillPersonBundle/config/services/repository.yaml
+++ b/src/Bundle/ChillPersonBundle/config/services/repository.yaml
@@ -12,3 +12,9 @@ services:
         factory: ['@doctrine.orm.entity_manager', getRepository]
         arguments:
             - 'Chill\PersonBundle\Entity\AccompanyingPeriod\ClosingMotive'
+
+    Chill\PersonBundle\Repository\AccompanyingPeriodRepository:
+        class: Chill\PersonBundle\Repository\AccompanyingPeriodRepository
+        tags: [ doctrine.repository_service ]
+        arguments:
+            - '@Doctrine\Persistence\ManagerRegistry'
diff --git a/src/Bundle/ChillPersonBundle/config/validation.yaml b/src/Bundle/ChillPersonBundle/config/validation.yaml
index 814db0ee4..ba6d6b84d 100644
--- a/src/Bundle/ChillPersonBundle/config/validation.yaml
+++ b/src/Bundle/ChillPersonBundle/config/validation.yaml
@@ -27,9 +27,9 @@ Chill\PersonBundle\Entity\Person:
         gender:
                - NotNull:
                   groups: [general, creation]
-        accompanyingPeriods:
-              - Valid:
-                  traverse: true
+        #accompanyingPeriods:
+        #      - Valid:
+        #          traverse: true
         email:
              - Email:
                   groups: [general, creation]
diff --git a/src/Bundle/ChillPersonBundle/migrations/Version20210331084527.php b/src/Bundle/ChillPersonBundle/migrations/Version20210331084527.php
index c42da9874..9c379c4b0 100644
--- a/src/Bundle/ChillPersonBundle/migrations/Version20210331084527.php
+++ b/src/Bundle/ChillPersonBundle/migrations/Version20210331084527.php
@@ -24,12 +24,16 @@ final class Version20210331084527 extends AbstractMigration
         $this->addSql('ALTER TABLE persons_accompanying_periods RENAME TO chill_person_accompanying_period_participation');
         
         // 2
-        // NOT NECCESSARY $this->addSql('CREATE SEQUENCE chill_person_accompanying_period_participation_id_seq INCREMENT BY 1 MINVALUE 1 START 1');
+        // SERIAL automatically create sequence with NEXTVAL()
         $this->addSql('ALTER TABLE chill_person_accompanying_period_participation ADD COLUMN id SERIAL NOT NULL PRIMARY KEY');
-        // TO CHECK !! automatically complete missing values allowing not null clause
-        // but add strange "id serial (10) default nextval('chill_person_accompanying_period_participation_id_seq':: regclass )" in column definition
+        // drop NEXTVAL() in column definition
+        $this->addSql('ALTER TABLE chill_person_accompanying_period_participation ALTER id DROP DEFAULT');
         
         // 3
+        $this->addSql('ALTER TABLE chill_person_accompanying_period_participation ADD startDate DATE NOT NULL DEFAULT \'1970-01-01\'');
+        $this->addSql('ALTER TABLE chill_person_accompanying_period_participation ADD endDate DATE DEFAULT NULL');
+    
+        // 4
         $this->addSql('ALTER TABLE chill_person_accompanying_period_participation DROP CONSTRAINT fk_49a3871f217bbb47');
         $this->addSql('ALTER TABLE chill_person_accompanying_period_participation DROP CONSTRAINT fk_49a3871f550b0c53');
         $this->addSql('ALTER TABLE chill_person_accompanying_period_participation ADD CONSTRAINT FK_A59DF89F217BBB47 FOREIGN KEY (person_id) REFERENCES chill_person_person (id) NOT DEFERRABLE INITIALLY IMMEDIATE');
@@ -40,7 +44,7 @@ final class Version20210331084527 extends AbstractMigration
     
     public function down(Schema $schema) : void
     {
-        // 3
+        // 4
         $this->addSql('ALTER TABLE chill_person_accompanying_period_participation DROP CONSTRAINT FK_A59DF89F217BBB47');
         $this->addSql('ALTER TABLE chill_person_accompanying_period_participation DROP CONSTRAINT FK_A59DF89F550B0C53');
         $this->addSql('ALTER TABLE chill_person_accompanying_period_participation ADD CONSTRAINT fk_49a3871f217bbb47 FOREIGN KEY (person_id) REFERENCES chill_person_person (id) ON DELETE CASCADE NOT DEFERRABLE INITIALLY IMMEDIATE');
@@ -48,6 +52,10 @@ final class Version20210331084527 extends AbstractMigration
         $this->addSql('ALTER INDEX idx_a59df89f550b0c53 RENAME TO idx_49a3871f550b0c53');
         $this->addSql('ALTER INDEX idx_a59df89f217bbb47 RENAME TO idx_49a3871f217bbb47');
         
+        // 3
+        $this->addSql('ALTER TABLE chill_person_accompanying_period_participation DROP startDate');
+        $this->addSql('ALTER TABLE chill_person_accompanying_period_participation DROP endDate');
+        
         // 2
         $this->addSql('DROP SEQUENCE chill_person_accompanying_period_participation_id_seq CASCADE');
         $this->addSql('ALTER TABLE chill_person_accompanying_period_participation DROP id');