This is a very simple application which I started as a replacement to the previous XML viewer. It is written using C# .NET 4.0 and WPF adhering to Model View View Model (MVVM) principles. If you download the source you can see the use of INotifyPropertyChanged for the view models as well as binding of properties between a view and its’ view model. Finally it starts using the ICommand interface to facilitate callbacks between view and view model. I have also tried to split the code into business logic and data access to decouple the classes as much as possible.