diff --git a/include/boost/fusion/sequence/adapted/mpl/tag_of.hpp b/include/boost/fusion/sequence/adapted/mpl/tag_of.hpp
deleted file mode 100644
index 756d94f6..00000000
--- a/include/boost/fusion/sequence/adapted/mpl/tag_of.hpp
+++ /dev/null
@@ -1,29 +0,0 @@
-/*=============================================================================
-    Copyright (c) 2001-2006 Joel de Guzman
-    Copyright (c) 2005-2006 Dan Marsden
-
-    Distributed under the Boost Software License, Version 1.0. (See accompanying 
-    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-==============================================================================*/
-#if !defined(BOOST_FUSION_TAG_OF_31122005_1153)
-#define BOOST_FUSION_TAG_OF_31122005_1153
-
-#include <boost/fusion/support/tag_of_fwd.hpp>
-#include <boost/fusion/support/detail/is_mpl_sequence.hpp>
-#include <boost/utility/enable_if.hpp>
-
-namespace boost { namespace fusion 
-{
-    struct mpl_sequence_tag;
-
-    namespace traits
-    {
-        template <typename Sequence>
-        struct tag_of<Sequence, typename boost::enable_if<detail::is_mpl_sequence<Sequence> >::type>
-        {
-            typedef mpl_sequence_tag type;
-        };
-    }
-}}
-
-#endif
diff --git a/include/boost/fusion/support/tag_of.hpp b/include/boost/fusion/support/tag_of.hpp
index ce8e0aeb..c7cfbb76 100644
--- a/include/boost/fusion/support/tag_of.hpp
+++ b/include/boost/fusion/support/tag_of.hpp
@@ -12,7 +12,9 @@
 #include <boost/fusion/support/detail/is_mpl_sequence.hpp>
 #include <boost/mpl/has_xxx.hpp>
 #include <boost/utility/enable_if.hpp>
+#include <boost/mpl/identity.hpp>
 #include <boost/mpl/bool.hpp>
+#include <boost/mpl/if.hpp>
 #include <utility>
 
 namespace boost
@@ -38,6 +40,7 @@ namespace boost
 namespace boost { namespace fusion
 {
     struct non_fusion_tag;
+    struct mpl_sequence_tag;
 
     namespace detail
     {
@@ -48,9 +51,10 @@ namespace boost { namespace fusion
     {
         template <typename Sequence, typename Active>
         struct tag_of
-        {
-            typedef non_fusion_tag type;
-        };
+          : mpl::if_< detail::is_mpl_sequence<Sequence>,
+              mpl::identity<mpl_sequence_tag>,
+              mpl::identity<non_fusion_tag> >::type
+        { };
 
         template <typename Sequence>
         struct tag_of<Sequence, typename boost::enable_if<detail::has_fusion_tag<Sequence> >::type>
@@ -73,9 +77,6 @@ namespace boost { namespace fusion
         template <typename T, std::size_t N>
         struct tag_of<boost::array<T, N> >;
 
-        template <typename Sequence>
-        struct tag_of<Sequence, typename boost::enable_if<detail::is_mpl_sequence<Sequence> >::type>;
-
         template<typename T1, typename T2>
         struct tag_of<std::pair<T1, T2> >;
     }