When we’re building WCF services, we often want to debug our code.  Creating a harness to host our service is easy enough but I’ve seen people open two instances of Visual Studio to do this.  One to host and one to debug.  However, that’s not necessary.  The trick is to go to the Solution properties and set the “Multiple start up projects” and select which ones you wish to start.  In my example, I have created a simple WCF service project, a project to contain my service contract, a console app to host the service in for testing and finally a project to actually make the call to my service.  I can tell VS to start both my hosting program and my caller program by making the changes shown below.

Another way you could accomplish the same is to right click on the project you want to start, select debug and then select start new instance.

Happy Coding!!