diff --git a/include/boost/fusion/algorithm/iteration/accumulate.hpp b/include/boost/fusion/algorithm/iteration/accumulate.hpp
index aa52a99b..b4d1e276 100644
--- a/include/boost/fusion/algorithm/iteration/accumulate.hpp
+++ b/include/boost/fusion/algorithm/iteration/accumulate.hpp
@@ -7,6 +7,7 @@
 #if !defined(FUSION_ACCUMULATE_09172005_1032)
 #define FUSION_ACCUMULATE_09172005_1032
 
+#include <boost/fusion/algorithm/iteration/accumulate_fwd.hpp>
 #include <boost/fusion/algorithm/iteration/fold.hpp>
 
 namespace boost { namespace fusion
diff --git a/include/boost/fusion/algorithm/iteration/accumulate_fwd.hpp b/include/boost/fusion/algorithm/iteration/accumulate_fwd.hpp
new file mode 100644
index 00000000..9c0bd115
--- /dev/null
+++ b/include/boost/fusion/algorithm/iteration/accumulate_fwd.hpp
@@ -0,0 +1,28 @@
+/*=============================================================================
+    Copyright (c) 2011 Eric Niebler
+
+    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_ACCUMULATE_FWD_HPP_INCLUDED)
+#define BOOST_FUSION_ACCUMULATE_FWD_HPP_INCLUDED
+
+namespace boost { namespace fusion
+{
+    namespace result_of
+    {
+        template <typename Sequence, typename State, typename F>
+        struct accumulate;
+    }
+
+    template <typename Sequence, typename State, typename F>
+    typename result_of::accumulate<Sequence, State const, F>::type
+    accumulate(Sequence& seq, State const& state, F f);
+
+    template <typename Sequence, typename State, typename F>
+    typename result_of::accumulate<Sequence const, State const, F>::type
+    accumulate(Sequence const& seq, State const& state, F f);
+}}
+
+#endif
+
diff --git a/include/boost/fusion/algorithm/iteration/detail/fold.hpp b/include/boost/fusion/algorithm/iteration/detail/fold.hpp
index cf92a354..7d8eb334 100644
--- a/include/boost/fusion/algorithm/iteration/detail/fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/detail/fold.hpp
@@ -15,6 +15,7 @@
 #include <boost/fusion/sequence/intrinsic/end.hpp>
 #include <boost/fusion/sequence/intrinsic/empty.hpp>
 #include <boost/fusion/sequence/intrinsic/size.hpp>
+#include <boost/fusion/support/is_segmented.hpp>
 #include <boost/fusion/iterator/equal_to.hpp>
 #include <boost/fusion/iterator/deref.hpp>
 #include <boost/fusion/iterator/value_of.hpp>
@@ -347,53 +348,73 @@ namespace boost { namespace fusion
             type;
         };
 
-        template<int SeqSize, typename StateRef, typename It0, typename F>
+        template<int SeqSize, typename StateRef, typename Seq, typename F>
         struct BOOST_PP_CAT(BOOST_FUSION_FOLD_NAME,_impl)
         {
             typedef typename
                 BOOST_PP_CAT(
                     result_of_first_unrolled,BOOST_FUSION_FOLD_NAME)<
                     StateRef
-                  , BOOST_FUSION_FOLD_IMPL_FIRST_IT_META_TRANSFORM(It0)
+                  , BOOST_FUSION_FOLD_IMPL_FIRST_IT_META_TRANSFORM(
+                        typename result_of::BOOST_FUSION_FOLD_IMPL_FIRST_IT_FUNCTION<Seq>::type
+                    )
                   , F
                   , SeqSize
                 >::type
             type;
 
             static type
-            call(StateRef state, It0 const& it0, F f)
+            call(StateRef state, Seq& seq, F f)
             {
-                return BOOST_PP_CAT(unrolled_,BOOST_FUSION_FOLD_NAME)<
-                    type
-                  , SeqSize
-                >::call(state,BOOST_FUSION_FOLD_IMPL_FIRST_IT_TRANSFORM(it0),f);
+                typedef
+                    BOOST_PP_CAT(unrolled_,BOOST_FUSION_FOLD_NAME)<
+                        type
+                      , SeqSize
+                    >
+                unrolled_impl;
+
+                return unrolled_impl::call(
+                    state,
+                    BOOST_FUSION_FOLD_IMPL_FIRST_IT_TRANSFORM(
+                        fusion::BOOST_FUSION_FOLD_IMPL_FIRST_IT_FUNCTION(seq)),
+                    f);
             }
         };
 
-        template<typename StateRef, typename It0, typename F>
-        struct BOOST_PP_CAT(BOOST_FUSION_FOLD_NAME,_impl)<0,StateRef,It0,F>
+        template<typename StateRef, typename Seq, typename F>
+        struct BOOST_PP_CAT(BOOST_FUSION_FOLD_NAME,_impl)<0,StateRef,Seq,F>
         {
             typedef StateRef type;
 
             static StateRef
-            call(StateRef state, It0 const&, F)
+            call(StateRef state, Seq&, F)
             {
                 return static_cast<StateRef>(state);
             }
         };
+
+        template<typename Seq, typename State, typename F, bool IsSegmented>
+        struct BOOST_PP_CAT(result_of_, BOOST_FUSION_FOLD_NAME)
+          : BOOST_PP_CAT(BOOST_FUSION_FOLD_NAME,_impl)<
+                result_of::size<Seq>::value
+              , typename add_reference<
+                    typename add_const<State>::type
+                >::type
+              , Seq
+              , F
+            >
+        {};
     }
 
     namespace result_of
     {
         template<typename Seq, typename State, typename F>
         struct BOOST_FUSION_FOLD_NAME
-          : detail::BOOST_PP_CAT(BOOST_FUSION_FOLD_NAME,_impl)<
-                size<Seq>::value
-              , typename add_reference<
-                    typename add_const<State>::type
-                >::type
-              , typename BOOST_FUSION_FOLD_IMPL_FIRST_IT_FUNCTION<Seq>::type
+          : detail::BOOST_PP_CAT(result_of_, BOOST_FUSION_FOLD_NAME)<
+                Seq
+              , State
               , F
+              , traits::is_segmented<Seq>::type::value
             >
         {};
     }
@@ -408,7 +429,7 @@ namespace boost { namespace fusion
     {
         return result_of::BOOST_FUSION_FOLD_NAME<Seq,State const,F>::call(
             state,
-            fusion::BOOST_FUSION_FOLD_IMPL_FIRST_IT_FUNCTION(seq),
+            seq,
             f);
     }
 
@@ -422,7 +443,7 @@ namespace boost { namespace fusion
     {
         return result_of::BOOST_FUSION_FOLD_NAME<Seq const,State const,F>::call(
             state,
-            fusion::BOOST_FUSION_FOLD_IMPL_FIRST_IT_FUNCTION(seq),
+            seq,
             f);
     }
 
@@ -436,7 +457,7 @@ namespace boost { namespace fusion
     {
         return result_of::BOOST_FUSION_FOLD_NAME<Seq,State,F>::call(
             state,
-            fusion::BOOST_FUSION_FOLD_IMPL_FIRST_IT_FUNCTION(seq),
+            seq,
             f);
     }
 
@@ -450,7 +471,7 @@ namespace boost { namespace fusion
     {
         return result_of::BOOST_FUSION_FOLD_NAME<Seq const,State,F>::call(
             state,
-            fusion::BOOST_FUSION_FOLD_IMPL_FIRST_IT_FUNCTION(seq),
+            seq,
             f);
     }
 }}
diff --git a/include/boost/fusion/algorithm/iteration/ext_/fold_s.hpp b/include/boost/fusion/algorithm/iteration/detail/segmented_fold.hpp
similarity index 58%
rename from include/boost/fusion/algorithm/iteration/ext_/fold_s.hpp
rename to include/boost/fusion/algorithm/iteration/detail/segmented_fold.hpp
index ce0f7434..2371e189 100644
--- a/include/boost/fusion/algorithm/iteration/ext_/fold_s.hpp
+++ b/include/boost/fusion/algorithm/iteration/detail/segmented_fold.hpp
@@ -7,7 +7,7 @@
 #if !defined(BOOST_FUSION_FOLD_S_HPP_INCLUDED)
 #define BOOST_FUSION_FOLD_S_HPP_INCLUDED
 
-#include <boost/fusion/algorithm/iteration/fold.hpp>
+#include <boost/fusion/algorithm/iteration/fold_fwd.hpp>
 #include <boost/fusion/support/segmented_fold_until.hpp>
 
 namespace boost { namespace fusion { namespace detail
@@ -33,35 +33,27 @@ namespace boost { namespace fusion { namespace detail
             }
         };
     };
-}}}
 
-namespace boost { namespace fusion
-{
-    namespace result_of
+    // The default implementation of this lives in detail/fold.hpp
+    template <typename Sequence, typename State, typename Fun, bool IsSegmented>
+    struct result_of_fold;
+
+    template <typename Sequence, typename State, typename Fun>
+    struct result_of_fold<Sequence, State, Fun, true>
     {
-        template <typename Sequence, typename State, typename F>
-        struct fold_s
-          : result_of::segmented_fold_until<
+        typedef
+            typename result_of::segmented_fold_until<
                 Sequence,
                 State,
-                detail::segmented_fold_fun<F>
-            >
-        {};
-    }
+                segmented_fold_fun<Fun>
+            >::type
+        type;
 
-    template <typename Sequence, typename State, typename F>
-    typename result_of::fold_s<Sequence, State, F>::type
-    fold_s(Sequence& seq, State const& state, F const& f)
-    {
-        return fusion::segmented_fold_until(seq, state, detail::segmented_fold_fun<F>(f));
-    }
-
-    template <typename Sequence, typename State, typename F>
-    typename result_of::fold_s<Sequence const, State, F>::type
-    fold_s(Sequence const& seq, State const& state, F const& f)
-    {
-        return fusion::segmented_fold_until(seq, state, detail::segmented_fold_fun<F>(f));
-    }
-}}
+        static type call(State& state, Sequence& seq, Fun fun)
+        {
+            return fusion::segmented_fold_until(seq, state, segmented_fold_fun<Fun>(fun));
+        }
+    };
+}}}
 
 #endif
diff --git a/include/boost/fusion/algorithm/iteration/fold.hpp b/include/boost/fusion/algorithm/iteration/fold.hpp
index 347fb4f1..4b9d7d46 100644
--- a/include/boost/fusion/algorithm/iteration/fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/fold.hpp
@@ -10,6 +10,8 @@
 #ifndef BOOST_FUSION_ALGORITHM_ITERATION_FOLD_HPP
 #define BOOST_FUSION_ALGORITHM_ITERATION_FOLD_HPP
 
+#include <boost/fusion/algorithm/iteration/fold_fwd.hpp>
 #include <boost/fusion/algorithm/iteration/detail/fold.hpp>
+#include <boost/fusion/algorithm/iteration/detail/segmented_fold.hpp>
 
 #endif
diff --git a/include/boost/fusion/algorithm/iteration/fold_fwd.hpp b/include/boost/fusion/algorithm/iteration/fold_fwd.hpp
new file mode 100644
index 00000000..edb43e01
--- /dev/null
+++ b/include/boost/fusion/algorithm/iteration/fold_fwd.hpp
@@ -0,0 +1,52 @@
+/*=============================================================================
+    Copyright (c) 2011 Eric Niebler
+
+    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)
+==============================================================================*/
+
+#ifndef BOOST_FUSION_ALGORITHM_ITERATION_FOLD_FWD_HPP
+#define BOOST_FUSION_ALGORITHM_ITERATION_FOLD_FWD_HPP
+
+namespace boost { namespace fusion
+{
+    namespace result_of
+    {
+        template<typename Seq, typename State, typename F>
+        struct fold;
+    }
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::fold<
+        Seq
+      , State const
+      , F
+    >::type
+    fold(Seq& seq, State const& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::fold<
+        Seq const
+      , State const
+      , F
+    >::type
+    fold(Seq const& seq, State const& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::fold<
+        Seq
+      , State const
+      , F
+    >::type
+    fold(Seq& seq, State& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::fold<
+        Seq const
+      , State const
+      , F
+    >::type
+    fold(Seq const& seq, State& state, F f);
+}}
+
+#endif
diff --git a/include/boost/fusion/algorithm/iteration/iter_fold.hpp b/include/boost/fusion/algorithm/iteration/iter_fold.hpp
index 59cbfd8c..722d6ef8 100644
--- a/include/boost/fusion/algorithm/iteration/iter_fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/iter_fold.hpp
@@ -10,6 +10,7 @@
 
 #define BOOST_FUSION_ITER_FOLD
 
+#include <boost/fusion/algorithm/iteration/iter_fold_fwd.hpp>
 #include <boost/fusion/algorithm/iteration/detail/fold.hpp>
 
 #undef 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
new file mode 100644
index 00000000..96ff387d
--- /dev/null
+++ b/include/boost/fusion/algorithm/iteration/iter_fold_fwd.hpp
@@ -0,0 +1,52 @@
+/*=============================================================================
+    Copyright (c) 2011 Eric Niebler
+
+    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)
+==============================================================================*/
+
+#ifndef BOOST_FUSION_ALGORITHM_ITERATION_ITER_FOLD_FWD_HPP
+#define BOOST_FUSION_ALGORITHM_ITERATION_ITER_FOLD_FWD_HPP
+
+namespace boost { namespace fusion
+{
+    namespace result_of
+    {
+        template<typename Seq, typename State, typename F>
+        struct iter_fold;
+    }
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::iter_fold<
+        Seq
+      , State const
+      , F
+    >::type
+    iter_fold(Seq& seq, State const& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::iter_fold<
+        Seq const
+      , State const
+      , F
+    >::type
+    iter_fold(Seq const& seq, State const& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::iter_fold<
+        Seq
+      , State const
+      , F
+    >::type
+    iter_fold(Seq& seq, State& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::iter_fold<
+        Seq const
+      , State const
+      , F
+    >::type
+    iter_fold(Seq const& seq, State& state, F f);
+}}
+
+#endif
diff --git a/include/boost/fusion/algorithm/iteration/reverse_fold.hpp b/include/boost/fusion/algorithm/iteration/reverse_fold.hpp
index bb09db5d..2ee4fd96 100644
--- a/include/boost/fusion/algorithm/iteration/reverse_fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/reverse_fold.hpp
@@ -10,6 +10,7 @@
 
 #define BOOST_FUSION_REVERSE_FOLD
 
+#include <boost/fusion/algorithm/iteration/reverse_fold_fwd.hpp>
 #include <boost/fusion/algorithm/iteration/detail/fold.hpp>
 
 #undef 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
new file mode 100644
index 00000000..40546b53
--- /dev/null
+++ b/include/boost/fusion/algorithm/iteration/reverse_fold_fwd.hpp
@@ -0,0 +1,52 @@
+/*=============================================================================
+    Copyright (c) 2011 Eric Niebler
+
+    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)
+==============================================================================*/
+
+#ifndef BOOST_FUSION_ALGORITHM_ITERATION_REVERSE_FOLD_FWD_HPP
+#define BOOST_FUSION_ALGORITHM_ITERATION_REVERSE_FOLD_FWD_HPP
+
+namespace boost { namespace fusion
+{
+    namespace result_of
+    {
+        template<typename Seq, typename State, typename F>
+        struct reverse_fold;
+    }
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::reverse_fold<
+        Seq
+      , State const
+      , F
+    >::type
+    reverse_fold(Seq& seq, State const& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::reverse_fold<
+        Seq const
+      , State const
+      , F
+    >::type
+    reverse_fold(Seq const& seq, State const& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::reverse_fold<
+        Seq
+      , State const
+      , F
+    >::type
+    reverse_fold(Seq& seq, State& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::reverse_fold<
+        Seq const
+      , State const
+      , F
+    >::type
+    reverse_fold(Seq const& seq, State& state, F f);
+}}
+
+#endif
diff --git a/include/boost/fusion/algorithm/iteration/reverse_iter_fold.hpp b/include/boost/fusion/algorithm/iteration/reverse_iter_fold.hpp
index 80079f48..2931301f 100644
--- a/include/boost/fusion/algorithm/iteration/reverse_iter_fold.hpp
+++ b/include/boost/fusion/algorithm/iteration/reverse_iter_fold.hpp
@@ -11,6 +11,7 @@
 #define BOOST_FUSION_REVERSE_FOLD
 #define BOOST_FUSION_ITER_FOLD
 
+#include <boost/fusion/algorithm/iteration/reverse_iter_fold_fwd.hpp>
 #include <boost/fusion/algorithm/iteration/detail/fold.hpp>
 
 #undef 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
new file mode 100644
index 00000000..a28b4eec
--- /dev/null
+++ b/include/boost/fusion/algorithm/iteration/reverse_iter_fold_fwd.hpp
@@ -0,0 +1,52 @@
+/*=============================================================================
+    Copyright (c) 2011 Eric Niebler
+
+    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)
+==============================================================================*/
+
+#ifndef BOOST_FUSION_ALGORITHM_ITERATION_REVERSE_ITER_FOLD_FWD_HPP
+#define BOOST_FUSION_ALGORITHM_ITERATION_REVERSE_ITER_FOLD_FWD_HPP
+
+namespace boost { namespace fusion
+{
+    namespace result_of
+    {
+        template<typename Seq, typename State, typename F>
+        struct reverse_iter_fold;
+    }
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::reverse_iter_fold<
+        Seq
+      , State const
+      , F
+    >::type
+    reverse_iter_fold(Seq& seq, State const& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::reverse_iter_fold<
+        Seq const
+      , State const
+      , F
+    >::type
+    reverse_iter_fold(Seq const& seq, State const& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::reverse_iter_fold<
+        Seq
+      , State const
+      , F
+    >::type
+    reverse_iter_fold(Seq& seq, State& state, F f);
+
+    template<typename Seq, typename State, typename F>
+    typename result_of::reverse_iter_fold<
+        Seq const
+      , State const
+      , F
+    >::type
+    reverse_iter_fold(Seq const& seq, State& state, F f);
+}}
+
+#endif
diff --git a/test/algorithm/segmented_fold.cpp b/test/algorithm/segmented_fold.cpp
index 6375473e..d023cac8 100644
--- a/test/algorithm/segmented_fold.cpp
+++ b/test/algorithm/segmented_fold.cpp
@@ -9,7 +9,7 @@
 #include <iostream>
 #include <boost/detail/lightweight_test.hpp>
 #include <boost/fusion/container/vector/vector.hpp>
-#include <boost/fusion/algorithm/iteration/ext_/fold_s.hpp>
+#include <boost/fusion/algorithm/iteration/fold.hpp>
 #include <boost/fusion/container/generation/make_vector.hpp>
 #include "../sequence/tree.hpp"
 
@@ -31,7 +31,7 @@ process_tree(Tree const &tree)
     using namespace boost;
 
     std::stringstream str;
-    fusion::fold_s(tree, &str, write_string());
+    fusion::fold(tree, &str, write_string());
     std::string res = str.str();
 
     BOOST_TEST_EQ(res, "a b c 1 2 3 100 e f 0 B 1 h i 4 5 6 j k l ");
diff --git a/test/sequence/segmented_iterator_range.cpp b/test/sequence/segmented_iterator_range.cpp
index 55d9e33b..e7cfaf46 100644
--- a/test/sequence/segmented_iterator_range.cpp
+++ b/test/sequence/segmented_iterator_range.cpp
@@ -7,7 +7,7 @@
 ==============================================================================*/
 #include <sstream>
 #include <boost/detail/lightweight_test.hpp>
-#include <boost/fusion/algorithm/iteration/ext_/for_each_s.hpp>
+#include <boost/fusion/algorithm/iteration/for_each.hpp>
 #include <boost/fusion/algorithm/query/find_if.hpp>
 #include <boost/fusion/container/vector/vector.hpp>
 #include <boost/fusion/container/generation/make_vector.hpp>
@@ -59,7 +59,7 @@ process_tree(Tree const &tree)
     slice_t slice(si, fi);
 
     std::stringstream sout;
-    fusion::for_each_s(slice, ostream_fun(sout));
+    fusion::for_each(slice, ostream_fun(sout));
     BOOST_TEST((sout.str() == "100 e f 0 B "));
 }