We have a superman pup who is almost 2. At first he was a bit aggressive towards any other animal but I soon got that out of him with my other dogs I have at home, being a chihuahua, foxie and spaniel. I also have another greyhound that he gets along with very well. He has never shown any aggression towards another greyhound at the track and he is starting to show great improvement on the track. He is a bit of a freak and needs a lot of warming up before we even arrive at the track. I have found him to be so worked up and really wants the lure and at the same time well behaved towards handlers and children. I have not had an issue with him attacking anyone or another greyhound.