Hi. we have an 13 month male, intact, 47 lbs, English Bulldog named Diesel. Starting when he was approx 10 weeks old we went to a puppy class and playtime with Diesel and he did fantastic - learned a lot and played a lot. The trainer was alway very impressed with him and would often use him to help shy puppies to get acclimated to the group and used to playing with other dogs. It wasn't until he graduated to the older playtime class that we really saw a problem. He loves to play with people and with dogs however once he moved to the older group none of the other dogs wanted to play with him and many would come up and snap. Many dogs we meet in the pet store, on the street, at the park, at relatives and friends houses bare their teeth and try to fight him. He has never ever showed any aggression towards other dogs. My parents dogs will bare their teeth, snap at him and have their hair stand on end and he just gives signals that he wants to play. He has never growled, showed his teeth or fought back with another dog. Many people we meet at the dog park ask if their dog can meet ours and when we say it is ok the other dogs tend to get aggressive while Diesel wants to play. The other owners always apologize and say that this isn't normal behavior from their dogs. when ever we go anywhere with him we keep him on a leash (even at my parents and off leash parks) so that we can pull him out of any bad situations that may arise. Many dogs will come up to him even when we are holding his leash and pick fights (again, D never fights back but he doesn't cower either). We see Diesel as confident and playful. We just want to figure out what we can do so that he can play with other dogs again. Is there something that we can teach him so that he can approach other dogs so that the other dogs don't get aggressive? Is it because he isn't neutered? Is it because taller dogs don't respect him and shorter dogs know he outweighs him? These are just some suggestions that the vet, trainer, and other dog owners have suggested.