diff --git a/doc/algorithm.qbk b/doc/algorithm.qbk
index f47fce5c..975887a1 100644
--- a/doc/algorithm.qbk
+++ b/doc/algorithm.qbk
@@ -258,6 +258,22 @@ the first call) and [arg_desc] of `seq`.
     typename result_of_name_macro<Sequence const, State const, F>::type name_macro(
         Sequence const& seq, State const& initial_state, F f);
 
+    template<
+        typename Sequence,
+        typename State,
+        typename F
+        >
+    typename result_of_name_macro<Sequence, State, F>::type name_macro(
+        Sequence& seq, State& initial_state, F f);
+
+    template<
+        typename Sequence,
+        typename State,
+        typename F
+        >
+    typename result_of_name_macro<Sequence const, State, F>::type name_macro(
+        Sequence const& seq, State& initial_state, F f);
+
 [def seq_concept_macro [seq_concept]]
 [def arg_type_id_macro [arg_type_id]]
 [def arg_id_macro [arg_id]]
diff --git a/include/boost/fusion/algorithm/iteration/detail/fold.hpp b/include/boost/fusion/algorithm/iteration/detail/fold.hpp
index 22cb6ecd..ddc4d0af 100644
--- a/include/boost/fusion/algorithm/iteration/detail/fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/detail/fold.hpp
@@ -68,9 +68,7 @@ namespace boost { namespace fusion
               , typename result_of::BOOST_FUSION_FOLD_IMPL_NEXT_IT_FUNCTION<It>::type
               , boost::result_of<
                     F(
-                        typename add_reference<typename add_const<
-                            typename State::type
-                        >::type>::type,
+                        typename add_reference<typename State::type>::type,
                         BOOST_FUSION_FOLD_IMPL_INVOKE_IT_META_TRANSFORM(It const)
                     )
                 >
@@ -108,9 +106,7 @@ namespace boost { namespace fusion
                 typename result_of::BOOST_FUSION_FOLD_IMPL_NEXT_IT_FUNCTION<It>::type
               , boost::result_of<
                     F(
-                        typename add_reference<typename add_const<
-                            typename State::type
-                        >::type>::type,
+                        typename add_reference<typename State::type>::type,
                         BOOST_FUSION_FOLD_IMPL_INVOKE_IT_META_TRANSFORM(It const)
                     )
                 >
@@ -136,7 +132,7 @@ namespace boost { namespace fusion
               , BOOST_FUSION_FOLD_IMPL_FIRST_IT_META_TRANSFORM(
                     typename result_of::BOOST_FUSION_FOLD_IMPL_FIRST_IT_FUNCTION<Seq>::type
                 )
-              , add_reference<typename add_const<State>::type>
+              , add_reference<State>
               , F
             >
         {};
@@ -150,7 +146,7 @@ namespace boost { namespace fusion
                 BOOST_FUSION_FOLD_IMPL_FIRST_IT_META_TRANSFORM(
                     typename result_of::BOOST_FUSION_FOLD_IMPL_FIRST_IT_FUNCTION<Seq>::type
                 )
-              , add_reference<typename add_const<State>::type>
+              , add_reference<State>
               , F
             >(
                 typename result_of::size<Seq>::type()
@@ -199,7 +195,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::BOOST_FUSION_FOLD_NAME<
         Seq
-      , State const
+      , State
       , F
     >::type
     BOOST_FUSION_FOLD_NAME(Seq& seq, State& state, F f)
@@ -211,7 +207,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::BOOST_FUSION_FOLD_NAME<
         Seq const
-      , State const
+      , State
       , F
     >::type
     BOOST_FUSION_FOLD_NAME(Seq const& seq, State& state, F f)
diff --git a/include/boost/fusion/algorithm/iteration/fold.hpp b/include/boost/fusion/algorithm/iteration/fold.hpp
index 29748cd8..039e01c0 100644
--- a/include/boost/fusion/algorithm/iteration/fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/fold.hpp
@@ -22,7 +22,6 @@
 #include <boost/fusion/iterator/next.hpp>
 #include <boost/utility/result_of.hpp>
 #include <boost/core/enable_if.hpp>
-#include <boost/type_traits/add_const.hpp>
 #include <boost/type_traits/add_reference.hpp>
 
 #if !defined(BOOST_FUSION_DONT_USE_PREPROCESSED_FILES)
diff --git a/include/boost/fusion/algorithm/iteration/fold_fwd.hpp b/include/boost/fusion/algorithm/iteration/fold_fwd.hpp
index f8328e80..0dbac761 100644
--- a/include/boost/fusion/algorithm/iteration/fold_fwd.hpp
+++ b/include/boost/fusion/algorithm/iteration/fold_fwd.hpp
@@ -38,7 +38,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::fold<
         Seq
-      , State const
+      , State
       , F
     >::type
     fold(Seq& seq, State& state, F f);
@@ -47,7 +47,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::fold<
         Seq const
-      , State const
+      , State
       , F
     >::type
     fold(Seq const& seq, State& state, F f);
diff --git a/include/boost/fusion/algorithm/iteration/iter_fold.hpp b/include/boost/fusion/algorithm/iteration/iter_fold.hpp
index 952466a1..cff5b4ed 100644
--- a/include/boost/fusion/algorithm/iteration/iter_fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/iter_fold.hpp
@@ -22,7 +22,6 @@
 #include <boost/fusion/iterator/next.hpp>
 #include <boost/utility/result_of.hpp>
 #include <boost/core/enable_if.hpp>
-#include <boost/type_traits/add_const.hpp>
 #include <boost/type_traits/add_reference.hpp>
 
 #define BOOST_FUSION_ITER_FOLD
diff --git a/include/boost/fusion/algorithm/iteration/iter_fold_fwd.hpp b/include/boost/fusion/algorithm/iteration/iter_fold_fwd.hpp
index 6c595cf1..1d8543ca 100644
--- a/include/boost/fusion/algorithm/iteration/iter_fold_fwd.hpp
+++ b/include/boost/fusion/algorithm/iteration/iter_fold_fwd.hpp
@@ -38,7 +38,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::iter_fold<
         Seq
-      , State const
+      , State
       , F
     >::type
     iter_fold(Seq& seq, State& state, F f);
@@ -47,7 +47,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::iter_fold<
         Seq const
-      , State const
+      , State
       , F
     >::type
     iter_fold(Seq const& seq, State& state, F f);
diff --git a/include/boost/fusion/algorithm/iteration/reverse_fold.hpp b/include/boost/fusion/algorithm/iteration/reverse_fold.hpp
index f2d060f3..252ad308 100644
--- a/include/boost/fusion/algorithm/iteration/reverse_fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/reverse_fold.hpp
@@ -22,7 +22,6 @@
 #include <boost/fusion/iterator/prior.hpp>
 #include <boost/utility/result_of.hpp>
 #include <boost/core/enable_if.hpp>
-#include <boost/type_traits/add_const.hpp>
 #include <boost/type_traits/add_reference.hpp>
 
 #define BOOST_FUSION_REVERSE_FOLD
diff --git a/include/boost/fusion/algorithm/iteration/reverse_fold_fwd.hpp b/include/boost/fusion/algorithm/iteration/reverse_fold_fwd.hpp
index 42c8ac21..c5e24b34 100644
--- a/include/boost/fusion/algorithm/iteration/reverse_fold_fwd.hpp
+++ b/include/boost/fusion/algorithm/iteration/reverse_fold_fwd.hpp
@@ -38,7 +38,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::reverse_fold<
         Seq
-      , State const
+      , State
       , F
     >::type
     reverse_fold(Seq& seq, State& state, F f);
@@ -47,7 +47,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::reverse_fold<
         Seq const
-      , State const
+      , State
       , F
     >::type
     reverse_fold(Seq const& seq, State& state, F f);
diff --git a/include/boost/fusion/algorithm/iteration/reverse_iter_fold.hpp b/include/boost/fusion/algorithm/iteration/reverse_iter_fold.hpp
index 85abf12f..3276bbde 100644
--- a/include/boost/fusion/algorithm/iteration/reverse_iter_fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/reverse_iter_fold.hpp
@@ -21,7 +21,6 @@
 #include <boost/fusion/iterator/prior.hpp>
 #include <boost/utility/result_of.hpp>
 #include <boost/core/enable_if.hpp>
-#include <boost/type_traits/add_const.hpp>
 #include <boost/type_traits/add_reference.hpp>
 
 #define BOOST_FUSION_REVERSE_FOLD
diff --git a/include/boost/fusion/algorithm/iteration/reverse_iter_fold_fwd.hpp b/include/boost/fusion/algorithm/iteration/reverse_iter_fold_fwd.hpp
index 21d99dee..76f01863 100644
--- a/include/boost/fusion/algorithm/iteration/reverse_iter_fold_fwd.hpp
+++ b/include/boost/fusion/algorithm/iteration/reverse_iter_fold_fwd.hpp
@@ -38,7 +38,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::reverse_iter_fold<
         Seq
-      , State const
+      , State
       , F
     >::type
     reverse_iter_fold(Seq& seq, State& state, F f);
@@ -47,7 +47,7 @@ namespace boost { namespace fusion
     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
     inline typename result_of::reverse_iter_fold<
         Seq const
-      , State const
+      , State
       , F
     >::type
     reverse_iter_fold(Seq const& seq, State& state, F f);
diff --git a/test/algorithm/fold.hpp b/test/algorithm/fold.hpp
index 87a81a7c..997623ea 100644
--- a/test/algorithm/fold.hpp
+++ b/test/algorithm/fold.hpp
@@ -189,7 +189,7 @@ struct fold_test_n
                     >::type
                   , typename mpl::if_c<
                         !n
-                      , mpl::vector<mpl::int_<1>, mpl::int_<0> > const&
+                      , mpl::vector<mpl::int_<1>, mpl::int_<0> >&
                       , mpl::vector<mpl::int_<n+1>, mpl::int_<squares_sum> >
                     >::type
                 >