We bought Collar for our French bulldog puppy who was terrorizing our older boxers and causing fights. It definitely helps. Thanks Dog-e-Shop, We are very pleased to have found Dog-e-Shop for our 13-year old "puppy" (Cavalier King Charles Spaniel). She is a companion dog, accustomed to spending her days with 1-2 indulgent humans, except for walks and playtime when she sometimes sees other people's pets.