The Model-View-ViewModel design pattern is one of the best ways to build a maintainable and testable UI in Microsoft Silverlight or Windows Presentation Foundation. The MVVM pattern is emerging as one of the most popular ways to build XAML presentation layers. The Visual Studio 2010 XAML designer makes certain assumptions around data binding that improve productivity, but can make the use of MVVM challenging. This is particularly true if your goal is to never type any XAML by hand or have any code-behind a XAML form; goals any Silverlight or WPF developer should appreciate. In this session learn how to apply the MVVM pattern while fully leveraging the XAML designer, and so minimizing code and effort while maximizing productivity and long-term maintainability.