Hi, boost::serialization is wonderful. It has saved a massive amount of effort when adding XML based storage to an existing C++ drawing library. A very big thank you to the author and the team. Questions arising: 1. After one or two crash & burn cycles i discovered the need to register derived classes in the 'save through a virtual base class pointer' scenario. Right now this is done when saving to/loading from the archive. Is there an alternative to this method that ensures registration occurs automatically? i'm sure this is a FAQ but cannot find a definitive answer. i..e // XML archive boost::archive::xml_iarchive ia(ifs); // ensure derived types are registered - too easy to forget, what's the better way? ia.register_type(static_cast<CDiagramButton*>(NULL)); 2. Serializing to a binary storage should be a great way to implement undo/redo and clipboard functionality - has anyone found fame and fortune doing this? Cheers Jerry.