Many of these dogs are used as guard dogs. To protect home and family. The ones that we have owned do this very well. Our dogs are controlled by fence and on the rare occasions that they are outside of a fence they do have a shock collar on them. No stranger approaches our dogs unless we have a leash on them. They do sometimes react to strangers if suprised. We lock them up when children are around. We have never considered our dogs as vicious and we have never had any issues with our dogs attacking people. The guard type dogs are extremely dedicated, loyal, and protective of their owners. That's the part that attracts us to this type of dog. They are a potentially loaded gun and need to be watched no matter how warm and fluffy they seem to be. They are tremendous responsibility for a dog owner if cared for properly.