diff --git a/utsushi/utsushi/functional.hpp b/utsushi/utsushi/functional.hpp

index 1e84119..75fe20e 100644

--- a/utsushi/utsushi/functional.hpp

+++ b/utsushi/utsushi/functional.hpp

@@ -58,6 +58,7 @@ using NAMESPACE::bind;

 using NAMESPACE::function;

 using NAMESPACE::ref;

 using NAMESPACE::reference_wrapper;

+using namespace NAMESPACE::placeholders;

 }       // namespace utsushi