Welcome to the fourth part of this article series on strategies for designing your application for a multitude of different clients. In the first part, we’ve looked into the business case & some general concerns, and in the second part, we made a choice for a service layer: WCF RIA Services. In the third part, we’ve seen how we can use MEF for on demand loading & code reuse across different clients. However, I left out a few things in that article: loading the Views on demand (as it requires extensions to the Silverlight Navigation framework to navigate to Views in an assembly that’s loaded on demand), and loading multiple assemblies on demand (as we need an async component loader for that, to ensure we can load these assemblies at the same time instead of one by one). This article will deal with these two concerns.