One of the most common concerns with respect to Web Services generally and WSDL design in particular is, "Which comes first, the WSDL or the source code?" In other words, should you create a WSDL document first and then develop the back-end source code needed for the service, or should you just let your existing programming language development environment generate the WSDL for you automatically from your source code? This presentation will discuss the evolution of this ongoing debate, outline the differences between the two approaches, and provide analysis and commentary on which approach "wins" out in the end.