diff --git a/include/boost/lexical_cast.hpp b/include/boost/lexical_cast.hpp
index 94dbaf9..0acc094 100644
--- a/include/boost/lexical_cast.hpp
+++ b/include/boost/lexical_cast.hpp
@@ -69,6 +69,11 @@
     throw_exception(bad_lexical_cast(typeid(Source), typeid(Target)))
 #endif
 
+#if (defined(BOOST_LCAST_HAS_INT128) && !defined(__GNUC__)) || GCC_VERSION > 40700
+#define BOOST_LCAST_HAS_INT128
+#endif
+
+
 namespace boost
 {
     // exception used to indicate runtime lexical_cast failure
@@ -310,6 +315,11 @@ namespace boost {
         > {};
 #endif
 
+#ifdef BOOST_LCAST_HAS_INT128
+        template <> struct stream_char_common< boost::int128_type >: public boost::mpl::identity< char > {};
+        template <> struct stream_char_common< boost::uint128_type >: public boost::mpl::identity< char > {};
+#endif
+
 #if !defined(BOOST_LCAST_NO_WCHAR_T) && defined(BOOST_NO_INTRINSIC_WCHAR_T)
         template <>
         struct stream_char_common< wchar_t >
@@ -602,6 +612,10 @@ namespace boost {
         BOOST_LCAST_DEF(unsigned __int64)
         BOOST_LCAST_DEF(         __int64)
 #endif
+#ifdef BOOST_LCAST_HAS_INT128
+        BOOST_LCAST_DEF(boost::int128_type)
+        BOOST_LCAST_DEF(boost::uint128_type)
+#endif
 
 #undef BOOST_LCAST_DEF
 
@@ -1723,6 +1737,12 @@ namespace boost {
             bool operator<<(unsigned __int64 n)         { start = lcast_put_unsigned<Traits>(n, finish); return true; }
             bool operator<<(         __int64 n)         { return shl_signed(n); }
 #endif
+
+#ifdef BOOST_LCAST_HAS_INT128
+        bool operator<<(const boost::uint128_type& n)   { start = lcast_put_unsigned<Traits>(n, finish); return true; }
+        bool operator<<(const boost::int128_type& n)    { return shl_signed(n); }
+#endif
+
             bool operator<<(float val)                  { return shl_real_type(val, start, finish); }
             bool operator<<(double val)                 { return shl_real_type(val, start, finish); }
             bool operator<<(long double val)            {
@@ -1916,7 +1936,7 @@ namespace boost {
             }
 
 /************************************ OPERATORS >> ( ... ) ********************************/
-            public:
+        public:
             bool operator>>(unsigned short& output)             { return shr_unsigned(output); }
             bool operator>>(unsigned int& output)               { return shr_unsigned(output); }
             bool operator>>(unsigned long int& output)          { return shr_unsigned(output); }
@@ -1930,6 +1950,12 @@ namespace boost {
             bool operator>>(unsigned __int64& output)           { return shr_unsigned(output); }
             bool operator>>(__int64& output)                    { return shr_signed(output); }
 #endif
+
+#ifdef BOOST_LCAST_HAS_INT128
+            bool operator>>(boost::uint128_type& output)        { return shr_unsigned(output); }
+            bool operator>>(boost::int128_type& output)         { return shr_signed(output); }
+#endif
+
             bool operator>>(char& output)                       { return shr_xchar(output); }
             bool operator>>(unsigned char& output)              { return shr_xchar(output); }
             bool operator>>(signed char& output)                { return shr_xchar(output); }
@@ -2563,6 +2589,7 @@ namespace boost {
 
 #undef BOOST_LCAST_THROW_BAD_CAST
 #undef BOOST_LCAST_NO_WCHAR_T
+#undef BOOST_LCAST_HAS_INT128
 
 #endif // BOOST_LEXICAL_CAST_INCLUDED
 
diff --git a/test/lexical_cast_integral_types_test.cpp b/test/lexical_cast_integral_types_test.cpp
index b34cdc4..96fc20e 100644
--- a/test/lexical_cast_integral_types_test.cpp
+++ b/test/lexical_cast_integral_types_test.cpp
@@ -47,6 +47,10 @@
 #define BOOST_LCAST_NO_WCHAR_T
 #endif
 
+#if (defined(BOOST_LCAST_HAS_INT128) && !defined(__GNUC__)) || GCC_VERSION > 40700
+#define BOOST_LCAST_HAS_INT128
+#endif
+
 // Test all 65536 values if true:
 bool const lcast_test_small_integral_types_completely = false;
 
@@ -56,6 +60,8 @@ int const lcast_integral_test_counter=500;
 
 using namespace boost;
 
+
+
 void test_conversion_from_to_short();
 void test_conversion_from_to_ushort();
 void test_conversion_from_to_int();
@@ -68,6 +74,10 @@ void test_conversion_from_to_uintmax_t();
 void test_conversion_from_to_longlong();
 void test_conversion_from_to_ulonglong();
 #endif
+#ifdef BOOST_LCAST_HAS_INT128
+void test_conversion_from_to_int128();
+void test_conversion_from_to_uint128();
+#endif
 void test_integral_conversions_on_min_max();
 
 
@@ -87,6 +97,10 @@ unit_test::test_suite *init_unit_test_suite(int, char *[])
 #ifdef LCAST_TEST_LONGLONG
     suite->add(BOOST_TEST_CASE(&test_conversion_from_to_longlong));
     suite->add(BOOST_TEST_CASE(&test_conversion_from_to_ulonglong));
+#endif
+#ifdef BOOST_LCAST_HAS_INT128
+    suite->add(BOOST_TEST_CASE(&test_conversion_from_to_int128));
+    suite->add(BOOST_TEST_CASE(&test_conversion_from_to_uint128));
 #endif
     suite->add(BOOST_TEST_CASE(&test_integral_conversions_on_min_max));
 
@@ -372,7 +386,7 @@ struct restore_oldloc
 };
 
 template<class T>
-void test_conversion_from_to_integral()
+void test_conversion_from_to_integral_minimal()
 {
     char const zero = '0';
     signed char const szero = '0';
@@ -438,7 +452,12 @@ void test_conversion_from_to_integral()
         must_owerflow_str += '0';
         must_owerflow_negative_str += '0';
     }
+}
 
+template<class T>
+void test_conversion_from_to_integral()
+{
+    test_conversion_from_to_integral_minimal<T>();
     typedef std::numpunct<char> numpunct;
 
     restore_oldloc guard;
@@ -536,6 +555,19 @@ void test_conversion_from_to_ulonglong()
 
 #endif
 
+
+#ifdef BOOST_LCAST_HAS_INT128
+void test_conversion_from_to_int128()
+{
+    test_conversion_from_to_integral_minimal<boost::int128_type>();
+}
+
+void test_conversion_from_to_uint128()
+{
+    test_conversion_from_to_integral_minimal<boost::uint128_type>();
+}
+#endif
+
 void test_integral_conversions_on_min_max()
 {
     typedef std::numeric_limits<int> int_limits;