Ok, so I posted a question about this (getting correct harness, etc) in the Hello thread but I actually have more questions. My almost 12 month old sheltie is a barker/lunger at squirrels, birds, rabbits, cars, and occasionally airplanes (I think when they look like birds LOL). He does not chase anything people ride (skateboards, bikes, does not chase joggers, etc)--it seems to be only high prey drive. So far he is training well to turn attention to me outside for birds--if he stays calm, sits, and looks at me I click and treat. That has been great to keep him calm about 90% of the time in my yard with birds. Unfortunately, I cannot get his attention to generalize this behavior for the other stimuli. He is very good in large spaces, such as walks in the park, as long as those furry little monsters are at a good distance. So we practice attention on me there and he does well. But once fast moving targets get closer, he is very, very difficult to calm down, and become quite reactive. I haven't been able to move to where he can clearly see the stimuli. He is less biddable than my previous sheltie and requires constant training to maintain currently learned behaviors (I think he tries to see how far he can push). Otherwise, he is great. He loves all people, all dogs, and has never marked/had an accident, etc. But the lunging works my nerves.