Debugging a WCF Service
Following are the 3-different ways to start debugging a WCF service:

When you are debugging a client process that calls a service. Here debugger steps into the service also service does not have to be in the same solution as your client application.
When you are debugging a client process that requests to a service and here service must be a part of your solution.
When you are using Attach to Process to attach to currently running service. Here debugging begins inside the service.

Debugging with Visual Studio 2008
Using Visual …