Hi. To support the serialization of a class I don't want to change anything, I have added free save and load function. (See the test code below.) It compiles and appears to work. I have the following questions: * Is it OK to put the save & load definitions in a separate implementation file? * Is it OK to specify track_never in a cpp file? Will this cause problems if someone else tries to serialize a map<int, string> ? thanks! - Martin - global_serialization.h - // ... class MyComplexClass; // ... namespace boost { namespace serialization { // Declare save and load for MyComplexClass template<class Archive> void save(Archive & ar, const MyComplexClass& t, unsigned int version); template<class Archive> void load(Archive & ar, MyComplexClass& t, unsigned int version); } } // Split: BOOST_SERIALIZATION_SPLIT_FREE(MyComplexClass); ***** - complex_class_serialization.cpp - // ... #include "ComplexClass.h" // ... typedef std::map<int, std::string ser_map_t; BOOST_CLASS_TRACKING(ser_map_t, boost::serialization::track_never); namespace boost { namespace serialization { template<class Archive> void save(Archive & ar, const MyComplexClass& t, unsigned int version) { // the relevant information to be serialized for // instances of MyComplexClass can be represented // by a map<int, string> ser_map_t m; // ... fill m object from t object ar << m; // Serialize } template<class Archive> void load(Archive & ar, CBoxHandler & t, unsigned int version) { ser_map_t m; ar >> m; // ... init t object from m } } // namespace serialization } // namespace boost