diff --git a/include/boost/type_traits/add_const.hpp b/include/boost/type_traits/add_const.hpp
index 802696c..a9fb781 100644
--- a/include/boost/type_traits/add_const.hpp
+++ b/include/boost/type_traits/add_const.hpp
@@ -14,8 +14,6 @@
 
 namespace boost {
 
-BOOST_TT_INLINE_NS
-
 // * convert a type T to const type - add_const<T>
 // this is not required since the result is always
 // the same as "T const", but it does suppress warnings
@@ -43,7 +41,6 @@ BOOST_TT_INLINE_NS
       typedef T& type;
    };
 
-BOOST_TT_INLINE_NS_END
 } // namespace boost
 
 #endif // BOOST_TT_ADD_CONST_HPP_INCLUDED
diff --git a/include/boost/type_traits/detail/config.hpp b/include/boost/type_traits/detail/config.hpp
index c1c611f..ebb1dd6 100644
--- a/include/boost/type_traits/detail/config.hpp
+++ b/include/boost/type_traits/detail/config.hpp
@@ -67,18 +67,6 @@
 #define BOOST_BROKEN_COMPILER_TYPE_TRAITS_SPECIALIZATION(x)
 #define BOOST_TT_BROKEN_COMPILER_SPEC(x)
 
-#ifdef BOOST_NO_CXX11_INLINE_NAMESPACES
-
-#define BOOST_TT_INLINE_NS
-#define BOOST_TT_INLINE_NS_END
-
-#else
-
-#define BOOST_TT_INLINE_NS  inline namespace BOOST_JOIN(tt, BOOST_VERSION) {
-#define BOOST_TT_INLINE_NS_END }
-
-#endif
-
 #endif // BOOST_TT_CONFIG_HPP_INCLUDED