>If there is no such way, does anyone know of a workaround, besides defining the properties before loading the class? There's an FLL floating around called AddProp that does what you want although this is not proper OO design <s>... As was suggested by Edward a good way to do this is to use Collections and add key/value pairs to them whenever you need new property values. I've also used a state table that uses a file to more permanently store state information, which is useful for Web applications when tracking users through a site. Regards,