What the 2026 Frontiers Study Says About Ethical Dog Training Methods

The Loudest Debate in Dog Training, Finally Studied

If you have spent ten minutes researching puppy training online, you have walked into the middle of an argument. On one side are force-free trainers with large followings. On the other are so-called balanced trainers like Cesar Millan and the account known as The Dog Daddy, each with three to four million YouTube subscribers, demonstrating prong collars and leash corrections. For a new puppy owner trying to choose a class, the noise is genuinely confusing. Both sides sound confident. Both claim results.

A study published in Frontiers in Veterinary Science in early 2026 steps back from the shouting and asks a quieter question: what do professional trainers themselves believe about ethics and evidence, and where do they actually agree? Researchers Jamie DeLeeuw and Todd Williams interviewed working trainers in depth, and the results give puppy owners something the comment sections never will. They offer a clear-eyed map of the disagreement, and of what the science underneath it really says.

What the Researchers Actually Did

This was a mostly qualitative study, which means its core data came from long, structured interviews rather than a quick poll. The team used stratified sampling to recruit 35 trainers, all affiliated with independent certification directories, and deliberately split them into two groups: 17 who described themselves as reward-based and 18 who described themselves as mixed methods. Each completed a pre-screen survey and then a semi-structured interview about how they think, not just what they do.

That design matters. Instead of counting who owns a clicker versus a shock collar, the researchers dug into the reasoning behind the choices. They looked at how trainers weigh a dog’s welfare, how they interpret scientific evidence, and how they feel about the fact that their own profession has almost no regulation. The result is less a scoreboard and more a portrait of how thoughtful practitioners on both sides actually arrive at their methods.

Where Every Trainer Agreed

Here is the finding that should reassure any new owner. Across both camps, trainers named positive reinforcement as the method they use most often and consider most effective. Even the mixed methods group, who keep aversive tools in their kit, reported reaching for rewards first. Everyone in the study expressed a strong commitment to dogs’ emotional well-being and to educating owners rather than just drilling dogs.

They also shared a worry. Dog training is unregulated in most of the United States, meaning anyone can print a business card and call themselves a trainer tomorrow with zero education required. Trainers on both sides of the method divide flagged this as a real problem for the field and for the dogs who pass through it. That concern is exactly why verifying an instructor’s credentials matters so much, a point worth keeping front of mind when you are choosing the right puppy class.

A small group of puppies and their owners working with treats in a bright indoor puppy training class

Where the Two Camps Split

The agreement ends when you ask why a method is acceptable. The reward-based trainers tended to ground their work in behavioral science and in what philosophers call deontological ethics, the idea that intentionally causing a dog fear or pain is wrong as a matter of principle, almost regardless of the outcome. For them, the line is the line.

The mixed methods trainers reasoned differently. They leaned toward consequentialist thinking, judging a method by its results in a specific situation, and they were more willing to use aversive tools when they believed the context justified it. They also placed more weight on hands-on practitioner experience than on published studies when deciding what counts as evidence.

One result from this group is quietly revealing. Although mixed methods trainers said they use positive reinforcement most often, when asked to rate effectiveness independently they scored positive punishment and positive reinforcement as equally effective. In other words, their stated preference for rewards was not fully matched by their belief that rewards work better, which leaves the door open to reaching for an aversive correction under pressure. For a puppy owner, that gap is the practical reason method labels alone are not enough.

What the Evidence Base Actually Shows

The study is honest about the science, and so should we be. The large body of research comparing approaches consistently links reward-based training to fewer behavior problems, less aggression, and lower fear and stress, with effectiveness equal to or better than aversive techniques. On the strength of that pattern, the American Veterinary Society of Animal Behavior recommends that dog training rely exclusively on reward-based methods.

The catch is that most of these studies are correlational, drawn from convenience samples, which makes airtight cause-and-effect claims harder to prove. There is only one published randomized controlled trial to date, and it compared an electronic collar to food rewards for stopping dogs from chasing a lure. The collar-trained dogs did stop the behavior quickly, but they were also the only dogs in the study to yelp during training, and the trial had real design flaws. So the picture is a broad, consistent welfare warning against aversive tools, paired with a researcher’s honest note that the field needs stronger studies. Notably, the imperfect evidence has not pushed the veterinary behavior establishment toward aversive methods. It has reinforced reward-based recommendations.

A hand holding a clicker and training treats while an eager puppy looks up, ready to be rewarded

The Tools the Research Warns About

When trainers and studies talk about aversive methods, these are the tools they mean. A prong collar pinches a dog’s neck when it pulls and releases when the dog stops. An electronic or shock collar (e-collar) delivers a static shock. An alpha roll forces a dog onto its back to assert dominance, a practice rooted in long-debunked wolf-pack theory. Each one works by adding something unpleasant, which is precisely the welfare risk the research keeps flagging.

The alternative the study describes is the LIMA framework, short for Least Intrusive, Minimally Aversive, often paired with the Humane Hierarchy. Rather than starting with a correction, LIMA starts by checking the dog’s well-being and adjusting the environment, then builds behavior through reinforcement, including rewarding the absence of a problem or teaching a replacement habit, such as a sit that makes jumping impossible. It is the same logic behind a good desensitization and counterconditioning plan for a fearful puppy, and it depends on knowing which rewards your individual dog values, which is why a quick preference test to find what truly motivates your puppy is time well spent before class even begins.

A joyful dog on a leash enjoys a walk with its owner on a wooden boardwalk. — Photo by gabesdotphotos on Pexels.

Questions to Ask Before You Enroll

The study’s deeper lesson is that a label like force-free or balanced only tells you so much. The reasoning behind it tells you more. Use these questions when you interview a prospective puppy class instructor:

What happens when a puppy gets something wrong? Listen for redirection and management, not correction or punishment.
What tools do you use, and which do you refuse to use? A clear no to prong collars, e-collars, and alpha rolls is the answer you want.
What are your certifications? Look for credentials from the CCPDT, the IAABC, or the Karen Pryor Academy, all of which require education and a code of ethics.
Do you follow LIMA or a humane hierarchy? A confident trainer will know the term and explain how they apply it.
Can I observe a class first? Transparency is a good sign; a refusal is a warning.

A good instructor welcomes every one of these questions. Defensiveness is itself an answer.

The Bottom Line

The 2026 Frontiers study does not crown a winner in the training wars, and it does not pretend the evidence is flawless. What it does, valuably, is show that even trainers who keep aversive tools on the shelf reach for rewards first, that the veterinary science community is united behind reward-based methods, and that the real fault line is ethical reasoning, not effectiveness. For your puppy, the takeaway is simple. Choose an instructor who can explain not just what they do but why, who treats your puppy’s emotional state as the starting point, and who earns your trust during that critical early socialization window. If you are still deciding whether a class is worth it at all, the developmental case for enrolling early in a positive reinforcement class is stronger than ever, and worth weighing against what a quality class actually costs.