Hello, I am hoping someone could answer a question I have regarding the make_nvp(..) function of the Serialization library. I am attempting to serialize a number of objects within a loop, and the name of the name-value-pair is to be assigned dynamically depending on some values taken from within the object that is to be serialized. I am currently performing the actions below: my_obj = GetMyObj(..); std::string temp = str( boost::format("x:%1% y:%2%") % _x % _y ); const char* const_temp = temp.c_str( ); ar & boost::serialization::make_nvp(const_temp, my_obj); This code compiles but will cause an exception on make_nvp. As far as I can tell, I am providing the function with the const char* that it requires, so am very confused as to why it is not performing as expected. Any help with this would be greatly appreciated. John Hammond ******************************************************************** This email and any attachments are confidential to the intended recipient and may also be privileged. If you are not the intended recipient please delete it from your system and notify the sender. You should not copy it or use it for any purpose nor disclose or distribute its contents to any other person. ********************************************************************