Hey everyone I have a white GSD that is about 2 years and 3 months old. I am looking to find someone who specializes in aggression. He is perfect with my girlfriend and I but anyone else he immediately perceives as a threat. Hes known my room mate his entire life and attacked him today. This is not the first instance of this and need to get it under control. He is good with other dogs but will still lunge at them on leash or at people. Saying my name itself is heiracy to this dog and you immediately hear a grumble from my dog. Even with friends ges known since he was little he is skeptical of still. **** run up to them and allow them to pet him, and 5 seconds later hes growling at them and I gotta restrain him. It's as if he doesnt know what to do. The attack on my room mate came completely out of the blue this morning. We were talking face to face and he just went nuts on him. I ripped him off, yelled at him, and put him in the kitchen and then I see him smiling 20 seconds later like nothing happened. Open the gate and then hes trying to play with the room mate he just bit. I'm willing to go far if it means I can get him the help he needs and so I dont gotta give him up if a kid ever comes into the picture. Please help.