Using WSDL in SOAP Applications
- Provides an overview of WSDL, history and background of various related technologies such as SOAP, and UDDI. By Uche Ogbuji, Fourthought, Inc.
- http://www-128.ibm.com/developerworks/webservices/library/ws-soap/index.html?dwzone=ws

A Busy Developer's Guide to SOAP
- Describes a subset of SOAP 1.1 that forms a basis for easy interoperation between different environments.
- http://www.soapware.org/bdg

Gentle Introduction To SOAP
- This document provides an introduction to the SOAP protocol. Only a basic knowledge of what a procedure call is and some familiarity with XML is required.
- http://www.intertwingly.net/stories/2002/03/16/aGentleIntroductionToSoap.html

Real SOAP Security
- Article by Matt Powell on MSDN. Despite the fact that SOAP as we know it today has no real support for security, there are secure XML Web Services in existence today.
- http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dn_voices_webservice/html/service11212001.asp