Training a German Shepherd?

To tell you the truth, you shouldn't train your pet for protection training. You'll just be playing with fire. It's a dangerous situation to have a dog with that particular training in your household. For example, my uncle is a police officer with the K-9 unit and he can't take his partner home because it's the dogs job to protect him. What would happen if you and your girlfriend got into a fight. The dog doesn't have the essment skills to differentiate the situation. All the dog sees is his partner in trouble. If you want your dog to protect you then don't do anything. Dogs can protect you just by being with you. They will deter people from mugging you or whatever.