If you walked into a pet store this afternoon and asked "what stops a dog from pulling on the leash," you'd very likely be handed a prong collar — a metal band of inward-facing pinch links that tightens on a dog's neck when they pull. The store would call it a "training collar." The packaging would show a calm, focused dog. The reality of how a prong collar works on a living animal is much harder to look at honestly, and it is the reason the leading veterinary behavior organizations in North America and Europe — including the American Veterinary Society of Animal Behavior (AVSAB), the American College of Veterinary Behaviorists (ACVB), and the British Veterinary Association — have all formally recommended against their use.
This is the case against prong collars, in plain terms.
What a prong collar actually does to a dog
A prong collar works by pain. That is not a value judgment; it is the operating principle. The inward-facing prongs apply concentrated pressure on the neck whenever the leash is tight. The pressure is meant to be aversive enough that the dog stops the behavior — usually pulling, lunging, or reactivity — to escape the discomfort. In the language of behavior science, this is positive punishment (adding something unpleasant to reduce a behavior) layered with negative reinforcement (the unpleasant thing stops when the dog complies).
The neck is one of the most vulnerable areas of a dog's body. It contains the trachea, the thyroid gland, the jugular veins, the cervical spine, and a dense network of lymph nodes. Veterinary case reports document a long list of injuries linked to repeated correction-collar use: tracheal collapse, laryngeal nerve damage, esophageal trauma, eye pressure spikes (in brachycephalic breeds especially), cervical disc injuries, and hairless or scarred patches of skin where prongs sat against the neck for years. None of these are rare in dogs who have worn one for any length of time.
Why "the dog stops pulling" is the wrong success metric
The most common defense of prong collars is that they "work." They do — the same way slamming on the brakes "works" to stop a car. The dog pulling on a prong collar usually does stop pulling, because pulling now hurts. This is not training. This is suppression.
Suppression has two well-documented problems:
1. It doesn't teach the dog what to do instead. A dog who has been corrected for pulling has learned that pulling causes pain. They have not learned that walking calmly beside you is rewarding, useful, or worth doing. Take the prong off and the pulling almost always returns — often with a fresh layer of leash anxiety on top.
2. It associates pain with whatever the dog was looking at. This is the most damaging side effect. If a dog gets a sharp prong correction every time they spot another dog across the street, they learn — accurately — that other dogs predict pain. Dogs that started out merely excited often turn into dogs that are genuinely reactive or aggressive after months on a prong collar. This effect, called counter-conditioning in reverse, is so well documented that it shows up in nearly every veterinary behaviorist's clinical caseload.
What the science actually says
Multiple peer-reviewed studies have compared aversive training tools (prongs, choke chains, shock collars) to reward-based methods. The summary is consistent across the literature: dogs trained with aversive tools show higher rates of stress-related behaviors (lip licking, yawning, paw lifts, whale eye, cortisol elevation), more pessimistic responses on cognitive bias tests, and either equal or worse outcomes on the actual training goal compared to dogs trained with food, play, or other rewards. None of the credible recent literature finds a unique benefit to prong collars that cannot be achieved with humane equipment and positive reinforcement.
"My trainer says they're fine if used correctly"
The "correct use" defense is the most common one, and it deserves a direct answer. The professional veterinary behavior community has reviewed the available evidence and concluded that there is no use case for the prong collar that cannot be addressed with safer equipment. A trainer who is recommending a prong collar in 2026 is choosing a tool that the credentialed scientific community has explicitly rejected. That is a meaningful signal about the trainer's methodology — see what to look for in a dog trainer and what to do if you've already hired a bad one.
What to do if you've been using a prong collar
You are not in trouble. The pet store sold it to you, the trainer recommended it, and the dog stopped pulling. You did what the people you trusted told you to do. Now you know more.
1. Switch to a properly fitted front-clip Y-harness — these redirect a pulling dog without putting any pressure on the throat.
2. Start over with a real loose-leash protocol. A reward-based trainer can have most dogs walking calmly within a few weeks; the behavioral solutions guide covers the basics.
3. Watch for the rebound. Dogs coming off long-term prong use often reactively explode the first few times they see another dog without the collar on. That is the suppressed reaction surfacing — a qualified trainer can guide you through the de-escalation work.
Where shelters and PawMates Pro fit in
Most shelters today screen for aversive-tool use during adoption interviews because they have seen, repeatedly, what happens when an adopter takes a sensitive shelter dog home and immediately puts a prong collar on them. Shelters that run on PawMates Pro record every dog's behavioral evaluation, fear triggers, and prior reactions on the pet profile, so adopters know up front whether the dog they're meeting is a candidate for sensitive handling. That information travels with the pet to the adopter dashboard, ready to share with whatever trainer or vet sees the dog next.
The bottom line is simple: there are gentler, faster, more durable ways to teach a dog to walk on a leash, stop reacting to other dogs, or recover from a rough start. Read the alternatives guide, and find a credentialed trainer who works without pain. Your dog will thank you, and the relationship you build will last.
Related reading
- Are prong collars illegal? — the legal picture in the U.S., Canada, and Europe.
- Is there a safe way to use prong collars and e-collars? — the answer the welfare evidence actually gives.
- Are e-collars cruel? — the parallel case on shock equipment.
For more adopter resources, browse the PawMates adopter blog.