diff --git a/turtle/detail/action.hpp b/turtle/detail/action.hpp
index 7d8ea77..4e45c59 100644
--- a/turtle/detail/action.hpp
+++ b/turtle/detail/action.hpp
@@ -12,6 +12,7 @@
 #include "../config.hpp"
 #include "lambda.hpp"
 #include <boost/type_traits/remove_reference.hpp>
+#include <boost/type_traits/is_convertible.hpp>
 #include <boost/type_traits/remove_const.hpp>
 #include <boost/utility/enable_if.hpp>
 #include <boost/shared_ptr.hpp>