diff --git a/tailbone/grids/filters.py b/tailbone/grids/filters.py
index 3a497d13..e136aa21 100644
--- a/tailbone/grids/filters.py
+++ b/tailbone/grids/filters.py
@@ -192,6 +192,17 @@ class GridFilter(object):
         """
         Set the value choices for the filter, post-construction.  Note that
         this also will set the value renderer to one which supports choices.
+
+        :param choices: A collection of "choices" for the filter.  This must be
+           in one of the following formats:
+
+           * simple list, each value of which should be a string, which is
+             assumed to be able to serve as both key and value (ordering of
+             choices will be preserved)
+           * simple dict, keys and values of which will define the choices
+             (note that the final choices will be sorted by key!)
+           * OrderedDict, keys and values of which will define the choices
+             (ordering of choices will be preserved)
         """
         # first must normalize choices
         if isinstance(choices, OrderedDict):