Validating XML SOAP request and response documents against XSD schemas leads to greater Web service security with only a modest effect on client performance. Microsoft's Xsd.exe is a versatile tool for generating XML schema from sample XML files. Apply this article's Heimlich maneuvers when Xsd.exe chokes on large, complex XML SOAP response documents. Test-drive the ASP.NET version of the article's downloadable Visual Basic .NET Windows form project at http://www.oakleaf.ws/xsdgen/.