I have a dog that barks constantly at people who are visiting and any little noise. nothing would stop her. The moment we put this on her she was a bit scared but quickly realized it was her bark causing the vibration and sound and stopped. now we put it on her when people are visiting and she is quiet. It also seems to be training her when it is not on because she only barks about 15% as much ash she used. This is a great easy to use product, set your levels, find a size for your dog and put it on. Enjoy a quiet home.