Hi, I very much want to use boost serialization but can't enable RTTI in my compiler (vc7/vc8) because of compatibility restrictions with other code. I've seen various statements on the web that boost serialization will work without RTTI, but no concrete instructions about how to make this happen. I've tried writing a trivial app using boost::archive::binary_oarchive, but I get this compiler warning (which is as good as an error): boost\smart_cast.hpp(76) : warning C4541: 'dynamic_cast' used on polymorphic type 'boost::archive::detail::basic_oarchive' with /GR-; unpredictable behavior may result So is it the case that, while serialization doesn't require RTTI, the provided archive classes do? Am I going to have to write my own archive class? Any help appreciated. cheers, os. -- os@collective.co.uk