Hi all, I'm trying to use the serialization library to serialize some classes. The least intrusive case is a headache because some of them don't even give me constructors I can access. The best would be to declare the serialize function as a friend of my class. For some reason it doesn't work. This is what I do in the class definition (inside namespace evt): friend class boost::serialization::access; template<class Archive> friend void ::boost::serialization::serialize( Archive & ar, Event & t, const unsigned int file_version); and this is what I do when I define the function: template<class Archive> void serialize( Archive & ar, evt::Event & t, const unsigned int file_version) { ar & BOOST_SERIALIZATION_NVP(t.fSEvent); }; Then I include both headers where I need to use them and allways get something like this: /home/JGonzalez/private/serialization/Event.h:24: `float evt::Event::fSEvent' is private /home/JGonzalez/private/serialization/SEventStreamers.h:32: within this context I don't know what I'm missing! I'm including both files. Does any one have an idea that could help me? thanks. Javier _______________________________ Do you Yahoo!? Express yourself with Y! Messenger! Free. Download now. http://messenger.yahoo.com