diff --git a/include/boost/fusion/container/set/detail/deref_impl.hpp b/include/boost/fusion/container/set/detail/deref_impl.hpp
index 12824e61..10a03496 100644
--- a/include/boost/fusion/container/set/detail/deref_impl.hpp
+++ b/include/boost/fusion/container/set/detail/deref_impl.hpp
@@ -36,7 +36,7 @@ namespace boost { namespace fusion { namespace extension
             static type
             call(It const& it)
             {
-                return at<typename It::index>(it.seq->get_data());
+                return ::boost::fusion::at<typename It::index>(it.seq->get_data());
             }
         };
     };