I tried my best to pull together a list of useful links related to implementing security within WCF services as recommended by the published patterns and practices.
Transport Layer Security Patterns and Practices (a little older but concepts are still relevant)
http://msdn.microsoft.com/en-us/library/ff650659.aspx
WCF Security Fundamentals Patterns and Practices
http://msdn.microsoft.com/en-us/library/ff649233.aspx
• WCF Security Fundamentals
• Authentication, Authorization, and Identities in WCF
• Impersonation and Delegation in WCF
• Message and Transport Security in WCF
Securing Services and Clients
http://msdn.microsoft.com/en-us/library/ms734736(v=VS.100).aspx
Message Security in WCF
http://msdn.microsoft.com/en-us/library/ms733137(v=VS.100).aspx
Use Transport Security and Message Credentials
http://msdn.microsoft.com/en-us/library/ms789011.aspx
Secure a Service with an X.509 Certificate
http://msdn.microsoft.com/en-us/library/ms788968.aspx
All of the content included in these links belongs to those companies and/or individuals. I am only providing links to the content as a way to find all of the information in one place.