diff --git a/src/risotto/message/message.py b/src/risotto/message/message.py
index 803e78d5..d49600f5 100644
--- a/src/risotto/message/message.py
+++ b/src/risotto/message/message.py
@@ -46,6 +46,7 @@ class MessageDefinition:
                  'uri',
                  'description',
                  'parameters',
+                 'default_roles',
                  'errors',
                  'pattern',
                  'related',
@@ -57,6 +58,7 @@ class MessageDefinition:
         self.parameters = OrderedDict()
         self.errors = []
         self.related = []
+        self.default_roles = []
         self.response = None
         self.uri = message