We used two methods.... First we try a sonic unit called BArk Free. It is a unic you can mount outsidenear your kennel or if he has the barkyard out your door. If that doesn't work we then used a bark collar along with the other unit. USE A BARK COLLOAR RESPONSIBLY !!!! You can injure a dog if you leave it on him and forgot about it so to speak. IF the dog is unresponsive to both then you need to definately find out why he is barking. Try kenneling him inside with the the bark free unit first that is how we train most of our dogs and we usually don't have to use a collar.