I will second what sbhkma said, it does take a lot of training, but if you are the pack leader to your dogs then "the pack mentality" works in your favor. If anyone's not sure what it means to be the pack leader, I would recommend researching and watching The Dog Whisperer. Ceaser Millan has done some amazing things with dogs and it's all with his "be the pack leader" mentality of training. Blew my mind when I watched it.