Ahh, the halcyon days of RPGLE - how I miss them (not!) ljv_az wrote: Everybody has a different opinion on what is the right way to do it. There's the clue to your dilemma; there is no 'right' way of doing WPF. You might decide to use MVVM or you might not - doesn't make it 'wrong'. In RPG you might use an 'if' or you might use one of those 'two-digits in a column that act like an if' things (it's been a while!) neither is 'wrong' it's often down to personal preference. (I had a manager who insisted on using the logic cycle in programs - but his reasons were, essentially, because that's what he was used to, coming from an RPG II background) My rule of thumb is to listen to the REASONS people give for doing things one way (or not doing them that way) and make your own mind up. Someone saying 'you shouldn't put any code in the code-behind' for example, is less than useless without the addition of a 'because...' If you listen to the 'because' bit you can then make up your own mind whether that's the 'right' way or not, and formulate your own rules; then next time someone criticises your code, you can respond with reasoned argument. I've MVVM# - See how I did MVVM my way ___________________________________________ Man, you're a god. - walterhevedeich 26/05/2011 .\\axxx (That's an 'M')