diff --git a/tailbone/grids/core.py b/tailbone/grids/core.py
index 5cb8f8d2..182c1a5c 100644
--- a/tailbone/grids/core.py
+++ b/tailbone/grids/core.py
@@ -109,8 +109,8 @@ class Grid(object):
         self.checked = checked
         if self.checked is None:
             self.checked = lambda item: False
-        self.main_actions = main_actions
-        self.more_actions = more_actions
+        self.main_actions = main_actions or []
+        self.more_actions = more_actions or []
 
         self._whgrid_kwargs = kwargs