diff --git a/integrator/interfaces.py b/integrator/interfaces.py
index 7909275..8421cb0 100644
--- a/integrator/interfaces.py
+++ b/integrator/interfaces.py
@@ -25,6 +25,7 @@ $Id$
 from zope.interface import Interface, Attribute
 from zope import interface, component, schema
 
+from loops.interfaces import IConceptSchema
 from loops.util import _
 
 
@@ -40,7 +41,7 @@ class IExternalSourceInfo(Interface):
 
 # external collections
 
-class IExternalCollection(Interface):
+class IExternalCollection(IConceptSchema):
     """ A concept representing a collection of resources that may be
         actively retrieved from an external system using the parameters
         given.