diff --git a/Form/Type/UserPickerType.php b/Form/Type/UserPickerType.php
index b253ce393..0d0a44fdd 100644
--- a/Form/Type/UserPickerType.php
+++ b/Form/Type/UserPickerType.php
@@ -87,34 +87,10 @@ class UserPickerType extends AbstractType
             ->setDefault('choice_label', function(User $u) {
                 return $u->getUsername();
             })
-            ->setNormalizer('query_builder', function(Options $options) {
-                $roles = $this->authorizationHelper->getParentRoles($options['role']);
-                $roles[] = $options['role'];
+            ->setNormalizer('choices', function(Options $options) {
                 
-                $qb = $this->userRepository->createQueryBuilder('u');
-                $qb
-                    // add center constraint
-                    ->join('u.groupCenters', 'ug')
-                    ->where($qb->expr()->eq('ug.center', ':center'))
-                    ->setParameter('center', $options['center'])
-                    // link to permission groups
-                    ->join('ug.permissionsGroup', 'pg')
-                    // role constraints
-                    ->join('pg.roleScopes', 'roleScope')
-                    ->andWhere($qb->expr()->in('roleScope.role', ':roles'))
-                    ->setParameter(
-                        'roles', 
-                        \array_map(
-                            function(Role $role) { return $role->getRole(); },
-                            $roles
-                        )
-                    )
-                    // add active constraint
-                    ->andWhere('u.enabled = :enabled')
-                    ->setParameter('enabled', true)
-                    ;
-
-                return $qb;
+                return $this->authorizationHelper
+                    ->findUsersReaching($options['role'], $options['center']);
             })
             ;
     }
diff --git a/Resources/config/services.yml b/Resources/config/services.yml
index 6cd323c56..c60212df5 100644
--- a/Resources/config/services.yml
+++ b/Resources/config/services.yml
@@ -59,8 +59,9 @@ services:
     chill.main.security.authorization.helper:
         class: Chill\MainBundle\Security\Authorization\AuthorizationHelper
         arguments:
-            - "@security.role_hierarchy"
-            - "%security.role_hierarchy.roles%"
+            $roleHierarchy: "@security.role_hierarchy"
+            $hierarchy: "%security.role_hierarchy.roles%"
+            $em: '@Doctrine\ORM\EntityManagerInterface'
     Chill\MainBundle\Security\Authorization\AuthorizationHelper: '@chill.main.security.authorization.helper'
             
     chill.main.role_provider:
diff --git a/Resources/translations/messages.fr.yml b/Resources/translations/messages.fr.yml
index bf082188f..543031d15 100644
--- a/Resources/translations/messages.fr.yml
+++ b/Resources/translations/messages.fr.yml
@@ -32,7 +32,7 @@ Confirm: Confirmer
 Cancel: Annuler
 Save: Enregistrer
 This form contains errors: Ce formulaire contient des erreurs
-
+Choose an user: Choisir un utilisateur
 'You are going to leave a page with unsubmitted data. Are you sure you want to leave ?': "Vous allez quitter la page alors que des données n'ont pas été enregistrées. Êtes vous sûr de vouloir partir ?"
 
 Edit: Modifier
diff --git a/Security/Authorization/AuthorizationHelper.php b/Security/Authorization/AuthorizationHelper.php
index 95552aa36..f786e38f3 100644
--- a/Security/Authorization/AuthorizationHelper.php
+++ b/Security/Authorization/AuthorizationHelper.php
@@ -27,6 +27,9 @@ use Symfony\Component\Security\Core\Role\RoleHierarchyInterface;
 use Symfony\Component\Security\Core\Role\Role;
 use Chill\MainBundle\Entity\Scope;
 use Chill\MainBundle\Security\RoleProvider;
+use Doctrine\ORM\EntityManagerInterface;
+use Chill\MainBundle\Entity\GroupCenter;
+use Chill\MainBundle\Entity\RoleScope;
 
 /**
  * Helper for authorizations. 
@@ -51,15 +54,20 @@ class AuthorizationHelper
      */
     protected $hierarchy;
     
-    protected $existingRoles = array('CHILL_MASTER_ROLE', 'CHILL_PERSON_SEE', 
-       'CHILL_PERSON_UPDATE',);
+    /**
+     *
+     * @var EntityManagerInterface
+     */
+    protected $em;
     
     public function __construct(
         RoleHierarchyInterface $roleHierarchy,
-        $hierarchy
+        $hierarchy,
+        EntityManagerInterface $em
     ) {
         $this->roleHierarchy = $roleHierarchy;
         $this->hierarchy     = $hierarchy;
+        $this->em = $em;
     }
     
     /**
@@ -219,7 +227,40 @@ class AuthorizationHelper
         return $scopes;
     }
     
-    
+    /**
+     * 
+     * @param Role $role
+     * @param Center $center
+     * @param Scope $circle
+     * @return Users
+     */
+    public function findUsersReaching(Role $role, Center $center, Scope $circle = null)
+    {
+        $parents = $this->getParentRoles($role);
+        $parents[] = $role;
+        $parentRolesString = \array_map(function(Role $r) { return $r->getRole(); }, $parents);
+        
+        $qb = $this->em->createQueryBuilder();
+        $qb
+            ->select('u')
+            ->from(User::class, 'u')
+            ->join('u.groupCenters', 'gc')
+            ->join('gc.permissionsGroup', 'pg')
+            ->join('pg.roleScopes', 'rs')
+            ->where('gc.center = :center')
+            ->andWhere($qb->expr()->in('rs.role', $parentRolesString))
+            ;
+        
+        $qb->setParameter('center', $center);
+        
+        if ($circle !== null) {
+            $qb->andWhere('rs.scope = :circle')
+                ->setParameter('circle', $circle)
+                ;
+        }
+        
+        return $qb->getQuery()->getResult();
+    }
     
     /**
      * Test if a parent role may give access to a given child role
diff --git a/Tests/Security/Authorization/AuthorizationHelperTest.php b/Tests/Security/Authorization/AuthorizationHelperTest.php
index fb171de07..3ed9a4b6f 100644
--- a/Tests/Security/Authorization/AuthorizationHelperTest.php
+++ b/Tests/Security/Authorization/AuthorizationHelperTest.php
@@ -459,6 +459,20 @@ class AuthorizationHelperTest extends KernelTestCase
             "Assert that `CHILL_MASTER_ROLE` is a parent of `CHILL_INHERITED_ROLE_1`");
     }
     
-    
+    public function testFindUsersReaching()
+    {
+        $centerA = static::$kernel->getContainer()
+            ->get('doctrine.orm.entity_manager')
+            ->getRepository(Center::class)
+            ->findOneByName('Center A');
+        
+        $users = $this->getAuthorizationHelper()
+            ->findUsersReaching(new Role('CHILL_PERSON_SEE'), 
+                $centerA);
+        
+        $usernames = \array_map(function(User $u) { return $u->getUsername(); }, $users);
+        
+        $this->assertContains('center a_social', $usernames);
+    }
     
 }