I have a 2 year old Aussie named Xena. She is always nipping at people! If people come in my house, even people that have been in my home before. She also does it at times when we are outside the home. She doesn't appear to be trying to hurt them, in fact she loves getting attention from them. It's getting out of hand because even though she isn't trying to hurt someone, she may and that's not a good thing. I've tried all different kinds of methods, like the treat method, distracting her, having people acknowledge her first for a few minutes when entering my home, etc... Nothing seems to calm her behavior, she continues to nip and jump on people the whole time they are at my house. I even have had to put her on a leash while we had visitors.