diff --git a/cof/admin.py b/cof/admin.py
index c62ae46e..fe531853 100644
--- a/cof/admin.py
+++ b/cof/admin.py
@@ -170,10 +170,11 @@ class UserProfileAdmin(UserAdmin):
     list_display = ('profile_num',) + UserAdmin.list_display \
         + ('profile_login_clipper', 'profile_phone', 'profile_occupation',
            'profile_mailing_cof', 'profile_mailing_bda',
-           'profile_mailing_bda_revente', 'is_cof', 'is_buro', )
+           'profile_mailing_bda_revente', 'is_buro', )
     list_display_links = ('username', 'email', 'first_name', 'last_name')
     list_filter = UserAdmin.list_filter \
-        + ('profile__cof__is_cof',
+        + (
+           # 'profile__cof__is_cof',
            'profile__cof__is_buro',
            'profile__cof__mailing',
            'profile__cof__mailing_bda')
diff --git a/cof/models.py b/cof/models.py
index 3ffdf365..d05fec3a 100644
--- a/cof/models.py
+++ b/cof/models.py
@@ -6,7 +6,7 @@ from __future__ import unicode_literals
 
 from django.db import models
 from django.dispatch import receiver
-from django.contrib.auth.models import User
+from django.contrib.auth.models import Group, Permission, User
 from django.utils.translation import ugettext_lazy as _
 from django.utils.encoding import python_2_unicode_compatible
 import django.utils.six as six
@@ -43,7 +43,6 @@ class CofProfile(models.Model):
     mailing = models.BooleanField("Recevoir les mails COF", default=False)
     # XXX. remove the following and use django auth.
     is_buro = models.BooleanField("Membre du Burô", default=False)
-    is_cof = models.BooleanField("Membre du COF", default=False)
     # XXX. remove the following and put in a BDA profile
     mailing_bda = models.BooleanField("Recevoir les mails BdA", default=False)
     mailing_bda_revente = models.BooleanField(
@@ -55,12 +54,25 @@ class CofProfile(models.Model):
         _("Remarques et précisions pour les petits cours"),
         blank=True, default="")
 
+
+    # is_cof = models.BooleanField("Membre du COF", default=False)
+    @property
+    def is_cof(self):
+        return self.profile.user.has_perm('cof.member')
+
+    @is_cof.setter
+    def is_cof(self, really):
+        if really:
+            g = Group.objects.get(name='cof_members')
+            self.groups.add(g)
+
+
     class Meta:
         verbose_name = "Profil COF"
         verbose_name_plural = "Profils COF"
 
     def __str__(self):
-        return self.user.username
+        return self.profile.user.username
 
 
 @python_2_unicode_compatible
diff --git a/cof/tests.py b/cof/tests.py
index 7ce503c2..15106223 100644
--- a/cof/tests.py
+++ b/cof/tests.py
@@ -1,3 +1,37 @@
+from django.contrib.auth.models import Group, Permission, User
+from django.contrib.contenttypes.models import ContentType
 from django.test import TestCase
 
-# Create your tests here.
+from cof.models import CofProfile
+
+from gestion.tests import create_profile
+
+def create_cofprofile(username):
+    p = create_profile(username)
+    return CofProfile.objects.create(profile=p)
+
+class TestCofProfile(TestCase):
+    def test_str(self):
+        # creates a group of cof members
+        group = Group.objects.create(name='cof_members')
+
+        # create a specific permission for all COF members.
+        ct = ContentType.objects.get(app_label='cof', model='CofProfile')
+        perm = Permission.objects.create(name='Cof Member',
+                                         codename='member',
+                                         content_type=ct)
+
+        # bind the two mutherfucker.
+        group.permissions = [perm]
+
+        # now test it for real
+        cofp = create_cofprofile('foo')
+        # XXX. should by default new CofProfiles be COF members?
+        self.assertFalse(cofp.profile.user.has_perm('cof.member'))
+        # adding/removing a user from the group should impact the
+        # permission
+        cofp.profile.user.groups.add(group)
+        cofp.save()
+
+        cofp = CofProfile.objects.first()
+        self.assertTrue(cofp.profile.user.has_perm('cof.member'))