diff --git a/ihatemoney/models.py b/ihatemoney/models.py
index b3d1395e..3c36e76c 100644
--- a/ihatemoney/models.py
+++ b/ihatemoney/models.py
@@ -22,15 +22,21 @@ class Project(db.Model):
 
     @property
     def _to_serialize(self):
-        return {
+        obj = {
             "id": self.id,
             "name": self.name,
             "contact_email": self.contact_email,
-            "members": self.members,
-            "active_members": self.active_members,
-            "balance": self.balance,
+            "members": [],
         }
 
+        balance = self.balance
+        for member in self.members:
+            member_obj = member._to_serialize
+            member_obj['balance'] = balance.get(member.id, 0)
+            obj['members'].append(member_obj)
+
+        return obj
+
     @property
     def active_members(self):
         return [m for m in self.members if m.activated]
diff --git a/ihatemoney/tests/tests.py b/ihatemoney/tests/tests.py
index 17b3a8d9..25f48ac9 100644
--- a/ihatemoney/tests/tests.py
+++ b/ihatemoney/tests/tests.py
@@ -1084,12 +1084,10 @@ class APITestCase(IhatemoneyTestCase):
 
         self.assertTrue(200, resp.status_code)
         expected = {
-            "active_members": [],
+            "members": [],
             "name": "raclette",
             "contact_email": "raclette@notmyidea.org",
-            "members": [],
             "id": "raclette",
-            "balance": {},
         }
         decoded_resp = json.loads(resp.data.decode('utf-8'))
         self.assertDictEqual(decoded_resp, expected)
@@ -1108,12 +1106,10 @@ class APITestCase(IhatemoneyTestCase):
 
         self.assertEqual(200, resp.status_code)
         expected = {
-            "active_members": [],
             "name": "The raclette party",
             "contact_email": "yeah@notmyidea.org",
             "members": [],
             "id": "raclette",
-            "balance": {},
         }
         decoded_resp = json.loads(resp.data.decode('utf-8'))
         self.assertDictEqual(decoded_resp, expected)
@@ -1449,21 +1445,15 @@ class APITestCase(IhatemoneyTestCase):
                               headers=self.get_auth("raclette"))
 
         expected = {
-            "active_members": [
-                {"activated": True, "id": 1, "name": "alexis", "weight": 1.0},
-                {"activated": True, "id": 2, "name": "freddy familly", "weight": 4.0},
-                {"activated": True, "id": 3, "name": "arnaud", "weight": 1.0}
+            "members": [
+                {"activated": True, "id": 1, "name": "alexis", "weight": 1.0, "balance": 20.0},
+                {"activated": True, "id": 2, "name": "freddy familly", "weight": 4.0, "balance": -20.0},
+                {"activated": True, "id": 3, "name": "arnaud", "weight": 1.0, "balance": 0},
             ],
-            "balance": {"1": 20.0, "2": -20.0, "3": 0},
             "contact_email": "raclette@notmyidea.org",
             "id": "raclette",
-
-            "members": [
-                {"activated": True, "id": 1, "name": "alexis", "weight": 1.0},
-                {"activated": True, "id": 2, "name": "freddy familly", "weight": 4.0},
-                {"activated": True, "id": 3, "name": "arnaud", "weight": 1.0}
-            ],
-            "name": "raclette"}
+            "name": "raclette",
+        }
 
         self.assertStatus(200, req)
         decoded_req = json.loads(req.data.decode('utf-8'))