The harness was a disaster with Dudley from the get-go. He would not walk at all when he was a puppy. I would put the harness on and try and walk him...my one neighbor would come out and watch because Dudley would go out the front door, stop dead and lay down. Would not budge! Even my bf could not get him to move. Tried for months...finally I put a collar on him...that was the end of the problem! He's so big, too, that the harness doesn't give me enough control with him...he doesn't pull against the collar.