The HSUS (Humane Society of the United States) provides the following comment on the use of aversive collars (choke chains, pinch collars and shock collars): "Some trainers use aversive collars to train "difficult" dogs with correction or punishment. These collars rely on physical discomfort or even pain to teach the dog what not to do. They suppress the unwanted behavior but don't teach him what the proper one is. At best, they are unpleasant for your dog, and at worst, they may cause your dog to act aggressively and even bite you. Positive training methods should always be your first choice." They go on to comment on shock collars specifically: "The least humane and most controversial use of the shock collar is as a training device. The trainer can administer a shock to a dog at a distance through a remote control. There is a greater chance for abuse (delivery of shocks as punishment) or misuse (poor timing of shocks). Your dog also may associate the painful shock with people or other experiences, leading to fearful or aggressive behavior".