>Since you are using a Window, why not move this from your Loaded event handler to a ContentRendered event handler.
That actually works! But I feel the event is orthogonal to validation and I'd rather not use it that way. In WinForms there was a reliable sequence that went ctor -> Loaded -> Activated. Quite often I'd have to put code in the first Activated event that would not work in Loaded, a classic being a call to Focus(). I can't find the equivalent yet for WPF. Greg
