1. German Shepherd German Shepherds are extremely intelligent, courageous, and have a very strong protective instinct (they are one of the best guard dogs). As long as they are trained in obedience from an early age by a loving but firm hand, they can be great family dogs, and excellent with children. Because of their intelligence, a German Shepherd needs a purpose or job in life to be truly happy. This intelligence, coupled with their courageous nature make German Shepherds excellent police and search dogs.