I have a wpf composite application with 3 or 4 modules that will always be loaded. In my shell I have a toolbar with buttons to active corresponding views from these modules. I injected an IEventAggregator into the shell presentor so that when a button is pressed I can publish an event that the corresponding module controller has subscribed to. When the event is caught the controllor will active its view.I have a wpf composite application with 3 or 4