diff --git a/flask_security/datastore/mongoengine.py b/flask_security/datastore/mongoengine.py
index dc61a18..39b7527 100644
--- a/flask_security/datastore/mongoengine.py
+++ b/flask_security/datastore/mongoengine.py
@@ -9,13 +9,13 @@ class MongoEngineUserDatastore(UserDatastore):
         self.db = db
         
         class Role(db.Document, RoleMixin):
-            name = db.StringField(required=True, max_length=80)
+            name = db.StringField(required=True, unique=True, max_length=80)
             description = db.StringField(max_length=255)
               
         class User(db.Document, UserMixin):
-            username = db.StringField(max_length=255)
-            email = db.StringField(max_length=255)
-            password = db.StringField(max_length=120)
+            username = db.StringField(unique=True, max_length=255)
+            email = db.StringField(unique=True, max_length=255)
+            password = db.StringField(required=True, max_length=120)
             active = db.BooleanField(default=True)
             roles= db.ListField(db.ReferenceField(Role), default=[])
             created_at = db.DateTimeField()