Well in the URL mapping, you can set things up to go directly to a view, in which case, you don't have a controller, but generally, I don't do that because you have a lot more flexibility when you have the controller code. I think even when you don't have a controller that one is created by the framework in the background, but you don't have direct access to it and would have to figure out where in the framework code to put a breakpoint if you wanted to debug it.