When a dog pulls excessively on leash, it is unpleasant for both the dog and the person walking him. Many people resort to yanking on their dogs, using pinch or choke collars, or stopping every few feet hoping for something to change.
Living with more than one dog can be a rewarding experience. Dogs love the company of other dogs. Knowing how to prevent problems and teaching dogs how to share resources so they do not bully each other, or pester you, is pivotal to having a harmonious multi-dog home.