Our 6-year-old Border Collie/Australian Shepard mix had never been leash trained, so while he was still decent, he wasn’t great and went too crazy at times. We have tried different leashes, but nothing ever seemed to work. This leash though actually worked. I was worried if it would slip off at first, but you know your dog can’t get out of it because it only gets tighter when they try to do so. I think our dog being a smart breed definitely made it easier, but us amateurs trying to train him to walk by us only took a week or so. Highly, highly recommended!