I'm convinced that it is a 'terrier' thing. I believe that they are harder to train than other breeds. I encourage you to continue reading through these blogs, I constantly pick-up things - like the size matters; the smaller the dog the longer it takes for them to get it - males appear to be easier than females, positive reinforcement - treats when they get it right, etc, and most of all, patience. Mitzi loves being outside. We are in a heavily wooded area and I cannot let her out unsupervised. This morning, at 5:30, I could hear the owls in the distance, of course Mitzi could care less. Terriers are tenacious.