In this chapter, you learned a variety of advanced SOAP techniques, including how to call web services asynchronously, how to enforce security, and how to gain support for new SOAP standards with the freely downloadable WSE toolkit. The world of web services is sure to continue to evolve in the future, so look for new standards and increasingly powerful capabilities to appear in future versions of the .NET Framework. For a more complete examination of the WSE, refer to Jeffrey Hasan’s book Expert Service-Oriented Architecture in C#: Using the Web Services Enhancements 2.0 (Apress, 2004).