Hi, I just came across this great Channel 9 web cast. It's on applied topic maps, and if you don't know what topic maps are then I'd highly recommend checking it out. To give you a quick intro, topic maps are a way of expressing strongly typed relationships between topics, and topics can be pretty much anything. They're a great way of expressing conceptual knowledge and relating it to the attributes that represent those concepts. So, they have many, many, many uses if you are dealing with data. You can find the webcast at: http://channel9.msdn.com/Showpost.aspx?postid=150161 Also, there's a web site explaining XML topic maps at: http://www.xtm.org (Note: it's been a few years since I last looked at this site. Hopefully it's still there.) Topic maps also have some great applications in accessibility. For example, I'm using one in a spare time research project investigating generating automatic description for video sequences. So, I'd highly recommend seeing what they're all about. Will