diff --git a/tailbone/views/master.py b/tailbone/views/master.py
index 685f989b..6a8a2d9d 100644
--- a/tailbone/views/master.py
+++ b/tailbone/views/master.py
@@ -1205,6 +1205,7 @@ class MasterView(View):
             else:
                 kwargs['cancel_url'] = self.get_row_action_url('view', instance)
 
+        kwargs.setdefault('session', self.Session())
         form = forms.AlchemyForm(self.request, fieldset, **kwargs)
         form.readonly = self.viewing
         return form