diff --git a/src/camps/mixins.py b/src/camps/mixins.py
index b3ec86be..ace90a55 100644
--- a/src/camps/mixins.py
+++ b/src/camps/mixins.py
@@ -28,16 +28,18 @@ class CampViewMixin(object):
                 filter_dict = {_filter: self.camp}
 
                 # get pk from kwargs if we have it
-                pk = self.kwargs.get(self.pk_url_kwarg)
-                if pk is not None:
-                    # We should also filter for the pk of the object
-                    filter_dict['pk'] = pk
+                if hasattr(self, 'pk_url_kwarg'):
+                    pk = self.kwargs.get(self.pk_url_kwarg)
+                    if pk is not None:
+                        # We should also filter for the pk of the object
+                        filter_dict['pk'] = pk
 
                 # get slug from kwargs if we have it
-                slug = self.kwargs.get(self.slug_url_kwarg)
-                if slug is not None and (pk is None or self.query_pk_and_slug):
-                    # we should also filter for the slug of the object
-                    filter_dict[self.get_slug_field()] = slug
+                if hasattr(self, 'slug_url_kwarg'):
+                    slug = self.kwargs.get(self.slug_url_kwarg)
+                    if slug is not None and (pk is None or self.query_pk_and_slug):
+                        # we should also filter for the slug of the object
+                        filter_dict[self.get_slug_field()] = slug
 
                 # do the filtering and return the result
                 result = queryset.filter(**filter_dict)