Hello Everyone, I recently inherited a 5 year old ACD from my parents (the shelters around here are kill shelters and they could not find another home for him), and he is living with my 2 year old lab who has some dog issues. They had been getting along very well until I took the ACD to my aunt's house without the lab. The ACD learned that he could control my aunt's ACD's every action with only his eyes (e.g., my aunt's dog would not enter any room my dog was in and would immediately drop anything he had in his mouth when my dog looked at him). When he came back home, he started herding/posturing/resource guarding the lab, including guarding the dog door. I have started feeding them in separate kennels and taking the lab for walks alone in the morning and running the ACD on a treadmill everyday. They are also fetched together at night. I've noticed that when these two start to have issues, the lab will roll on his back and then start to growl when the ACD doesn't leave him alone or will play bow and growl the entire time. Sometimes the ACD will leave the house and guard the door or the lab will run into his kennel in the living room. I've already taken the lab to the only 2 trainers in our area with no success (yahoo forums have helped us make the most progress). Also, I have been introducing the ACD to other dogs and he usually ignores them completely. Growing up, I always had dogs that were outdoor dogs only that lived in a kennel (that is what the ACD came from) so I am not sure how to handle this. Currently we use water to break up "fights" (no biting occurs) and sometimes have them both go into a down stay for 15 minutes or separate them until they have both calmed down. Any advice or book recommendations?? Thanks!! Amanda I forgot to mention that the lab has a history of being "dog reactive". He has improved significantly around dogs he knows and dogs he is introduced to off leash, but we are still working with on-leash which is why I walk them separately. I've been clicker training both of them using Sue's Training Levels.