I have a question to add. My dog is 10 weeks old. He used to nipping me and my family (3 people) all the time when he first got him at 5 weeks, but now he has gotten used to us and I have also trained him. Basically he knows the ground rules. He loves playing with my 2 year old kid and loves for my girl to rub him down. I take him to the dog park all the time and he loves playing with bigger dogs. He has gotten into it with some doors, but he never causes the problem. I guess the bigger dogs pick on him and he doesn't back down. Hes very game. He doesn't nip us at all anymore. A week ago though I had a problem with a slip chain....I just couldn't take it off. I tried pushing his head into the collar (while he was trying to get away) and he bit my right hand..hard and broke the skin. He let go asap. Since then he has been the same old him. I have read about fear biting and I think I caused it to happen. Am I right to think so? Would you classify that as fear biting or aggressiveness? And if it is fear biting does that basically mean that if I or a member of my family does something that makes him uncomfortable in the future we will get bit? Sorry for the long message.