Our 9 week old puppy absolutely LOVES her play pen. We use it for her naps and she loves dragging her toys in it to play throughout the day. It was an easy set up and we love the fact that you can take top off if you don't need it. I don't know what will happen when she gets bigger because w/o the top she can stand up and look over it but only time will tell (we may have to buy a bigger one). We also like that it is portable, we take it with us where ever we take her so she has a place of her own. I do recommend getting a nice soft blanket for the bottom since there isn't any cushion.