diff --git a/build/vc100/turtle.vcxproj b/build/vc100/turtle.vcxproj
index 944ccf1..f87da0f 100644
--- a/build/vc100/turtle.vcxproj
+++ b/build/vc100/turtle.vcxproj
@@ -41,7 +41,6 @@
     <ClInclude Include="..\..\turtle\detail\is_functor.hpp" />
     <ClInclude Include="..\..\turtle\detail\lambda.hpp" />
     <ClInclude Include="..\..\turtle\detail\object_impl.hpp" />
-    <ClInclude Include="..\..\turtle\detail\operators.hpp" />
     <ClInclude Include="..\..\turtle\detail\parameter.hpp" />
     <ClInclude Include="..\..\turtle\detail\parent.hpp" />
     <ClInclude Include="..\..\turtle\detail\root.hpp" />
diff --git a/build/vc100/turtle.vcxproj.filters b/build/vc100/turtle.vcxproj.filters
index e4ecc2e..cefd6a2 100644
--- a/build/vc100/turtle.vcxproj.filters
+++ b/build/vc100/turtle.vcxproj.filters
@@ -97,9 +97,6 @@
     <ClInclude Include="..\..\turtle\detail\invocation.hpp">
       <Filter>Source Files\detail</Filter>
     </ClInclude>
-    <ClInclude Include="..\..\turtle\detail\operators.hpp">
-      <Filter>Source Files\detail</Filter>
-    </ClInclude>
     <ClInclude Include="..\..\turtle\detail\object_impl.hpp">
       <Filter>Source Files\detail</Filter>
     </ClInclude>
diff --git a/test/test_constraints.cpp b/test/test_constraints.cpp
index f4aba81..ff2338b 100644
--- a/test/test_constraints.cpp
+++ b/test/test_constraints.cpp
@@ -7,7 +7,6 @@
 // http://www.boost.org/LICENSE_1_0.txt)
 
 #include <turtle/constraints.hpp>
-#include <turtle/detail/operators.hpp>
 #include <boost/test/auto_unit_test.hpp>
 
 BOOST_AUTO_TEST_CASE( all_comparison_constraints_can_be_instanciated )
diff --git a/turtle/constraint.hpp b/turtle/constraint.hpp
index a5326e6..01648db 100644
--- a/turtle/constraint.hpp
+++ b/turtle/constraint.hpp
@@ -22,6 +22,98 @@ namespace mock
         {}
         Constraint f_;
     };
+
+namespace detail
+{
+    template< typename Constraint1, typename Constraint2 >
+    class and_
+    {
+    public:
+        and_( const Constraint1& c1, const Constraint2& c2 )
+            : c1_( c1 )
+            , c2_( c2 )
+        {}
+        template< typename Actual >
+        bool operator()( const Actual& actual ) const
+        {
+            return c1_( actual ) && c2_( actual );
+        }
+        friend std::ostream& operator<<( std::ostream& s, const and_& a )
+        {
+            return s << "( " << mock::format( a.c1_ )
+                << " && " << mock::format( a.c2_ ) << " )";
+        }
+    private:
+        Constraint1 c1_;
+        Constraint2 c2_;
+    };
+
+    template< typename Constraint1, typename Constraint2 >
+    class or_
+    {
+    public:
+        or_( const Constraint1& c1, const Constraint2& c2 )
+            : c1_( c1 )
+            , c2_( c2 )
+        {}
+        template< typename Actual >
+        bool operator()( const Actual& actual ) const
+        {
+            return c1_( actual ) || c2_( actual );
+        }
+        friend std::ostream& operator<<( std::ostream& s, const or_& o )
+        {
+            return s << "( " << mock::format( o.c1_ )
+                << " || " << mock::format( o.c2_ )<< " )";
+        }
+    private:
+        Constraint1 c1_;
+        Constraint2 c2_;
+    };
+
+    template< typename Constraint >
+    class not_
+    {
+    public:
+        explicit not_( const Constraint& f )
+            : f_( f )
+        {}
+        template< typename Actual >
+        bool operator()( const Actual& actual ) const
+        {
+            return ! f_( actual );
+        }
+        friend std::ostream& operator<<( std::ostream& s, const not_& n )
+        {
+            return s << "! " << mock::format( n.f_ );
+        }
+    private:
+        Constraint f_;
+    };
+}
+
+    template< typename Constraint1, typename Constraint2 >
+    const constraint< detail::or_< Constraint1, Constraint2 > >
+        operator||( const constraint< Constraint1 >& lhs,
+                    const constraint< Constraint2 >& rhs )
+    {
+        return detail::or_< Constraint1, Constraint2 >( lhs.f_, rhs.f_ );
+    }
+
+    template< typename Constraint1, typename Constraint2 >
+    const constraint< detail::and_< Constraint1, Constraint2 > >
+        operator&&( const constraint< Constraint1 >& lhs,
+                    const constraint< Constraint2 >& rhs )
+    {
+        return detail::and_< Constraint1, Constraint2 >( lhs.f_, rhs.f_ );
+    }
+
+    template< typename Constraint >
+    const constraint< detail::not_< Constraint > >
+        operator!( const constraint< Constraint >& c )
+    {
+        return detail::not_< Constraint >( c.f_ );
+    }
 } // mock
 
 #define MOCK_UNARY_CONSTRAINT(N,Expr) \
diff --git a/turtle/detail/check.hpp b/turtle/detail/check.hpp
index e387375..3af3f10 100644
--- a/turtle/detail/check.hpp
+++ b/turtle/detail/check.hpp
@@ -9,7 +9,6 @@
 #ifndef MOCK_CHECK_HPP_INCLUDED
 #define MOCK_CHECK_HPP_INCLUDED
 
-#include "operators.hpp"
 #include "is_functor.hpp"
 #include "../log.hpp"
 #include <boost/utility/enable_if.hpp>