diff --git a/mellon/adapters.py b/mellon/adapters.py
index bbf56e1..a4dff9d 100644
--- a/mellon/adapters.py
+++ b/mellon/adapters.py
@@ -28,6 +28,9 @@ class DefaultAdapter(object):
                 return idp
 
     def get_identity_providers_setting(self):
+        if not app_settings.IDENTITY_PROVIDERS:
+            from django.core.exceptions import ImproperlyConfigured
+            raise ImproperlyConfigured('The MELLON_IDENTITY_PROVIDERS setting is mandatory')
         return app_settings.IDENTITY_PROVIDERS
 
     def get_idps(self):
diff --git a/mellon/app_settings.py b/mellon/app_settings.py
index b948a2f..131ba9c 100644
--- a/mellon/app_settings.py
+++ b/mellon/app_settings.py
@@ -45,8 +45,7 @@ class AppSettings(object):
         try:
             idps = settings.MELLON_IDENTITY_PROVIDERS
         except AttributeError:
-            from django.core.exceptions import ImproperlyConfigured
-            raise ImproperlyConfigured('The MELLON_IDENTITY_PROVIDERS setting is mandatory')
+            return []
         if isinstance(idps, dict):
             idps = [idps]
         return idps