How to Fit a Slip Lead Correctly (And Why I Was Horrified by Google's Answer)

I recently had a client ask me how to fit a slip lead correctly. No problem, I thought. I'll have a quick look online and send them a reliable article.

Instead, the very first thing Google AI suggested was that a slip lead should fit around the dog's neck and sit high behind the ears.

Honestly, I was horrified.

Not because that's what has traditionally been taught, but because it completely ignored everything we've learnt over the last few decades about canine learning, welfare and behaviour.

It reminded me how easy it is for outdated training advice to be presented as fact, especially when AI is pulling information from across the internet without considering whether it's current or evidence based.

What is a Slip Lead?

A slip lead is a lead and collar combined into one piece of equipment. Traditionally, they've been used in situations where dogs need to be moved quickly and safely, such as in veterinary practices, rescue centres, by working dog handlers or during emergencies.

Over the years, however, slip leads have become widely used as training tools, particularly for teaching loose lead walking.

This is where things become important.

Traditional slip lead training typically works through a combination of positive punishment (+P) followed by negative reinforcement (-R), as described within B.F. Skinner's theory of operant conditioning (Skinner, 1938).

When a dog reaches the end of the lead, pressure is applied to the neck as the slip lead tightens. The addition of that pressure is intended to reduce the pulling behaviour, known as positive punishment. As soon as the dog moves back towards the handler or returns to the desired position, the pressure is removed. The removal of that unpleasant stimulus reinforces the behaviour that caused it to disappear, known as negative reinforcement.

Over time, the dog learns how to avoid or escape that pressure by maintaining the desired position.

Historically, this has been accepted as a way of teaching loose lead walking. However, our understanding of canine learning, behaviour and welfare has developed significantly.

Our Understanding Has Changed

Modern dog training is not just about whether a dog learns. It asks how they learn and what that learning feels like.

We now know dogs do not need discomfort or physical pressure to acquire new skills. Instead, we can teach loose lead walking through positive reinforcement, environmental rewards, management and clear communication, helping dogs feel safe enough to learn rather than teaching them how to avoid discomfort.

Research consistently shows that reward based training is associated with improved welfare, lower stress levels and fewer behaviour problems when compared with aversive training methods (Ziv, 2017; Vieira de Castro et al., 2020).

How Should a Slip Lead Be Used?

From a welfare perspective, if a dog is wearing a slip lead, it should remain loose and should never apply constant pressure around the neck. Its purpose should be safe management or transport, not teaching through sustained pressure.

The neck contains incredibly delicate structures, including the:

• Trachea

• Larynx

• Thyroid gland

• Cervical vertebrae

• Major blood vessels

• Vagus nerve

• Muscles and soft tissues

  
  

Repeated or prolonged pressure on these structures has the potential to cause discomfort and, in some cases, injury. Research has demonstrated that pressure applied through collars can affect the tissues of the neck and even increase intraocular pressure in dogs (Pauli et al., 2006).

This is particularly relevant for dogs who pull, brachycephalic breeds, dogs with tracheal disease, cervical spinal conditions, or breeds predisposed to Intervertebral Disc Disease (IVDD), such as Dachshunds.

If we are already asking our dogs to navigate traffic, unfamiliar people, other dogs, cyclists, loud noises and countless other distractions, they are processing an enormous amount of information. The last thing they need is additional pressure around one of the most sensitive parts of their body.

We Can Teach Without Pressure

Loose lead walking is not about finding the right piece of equipment.

It is about teaching the dog the skills they need to make good choices.

That might include:

• Reinforcing walking beside us.

• Using environmental rewards such as access to sniffing.

• Building engagement with the handler.

• Teaching pattern games.

• Helping dogs regulate their emotions in challenging environments.

• Setting dogs up for success instead of expecting them to cope with situations they are not yet ready for.

Dogs learn best when they feel safe, when they understand what we are asking of them and when they are motivated to work with us. We do not need to rely on pressure around the neck to achieve reliable loose lead walking.

A Better Alternative: A Well Fitted Y-Shaped Harness

If your dog is still learning how to walk nicely on the lead, a well fitted Y-shaped harness is a much more welfare friendly option.

Unlike equipment that tightens around the neck, a Y-shaped harness distributes pressure across the chest and shoulders, reducing pressure on the delicate structures of the neck. This allows us to teach loose lead walking without relying on discomfort.

That doesn't mean a harness will stop pulling on its own. No piece of equipment teaches behaviour.

What it does do is give us the opportunity to teach our dogs safely while they are learning.

A well fitted Y-shaped harness should:

• Sit clear of the shoulder joints to allow a full range of movement.

• Form a "Y" shape across the front of the chest.

• Allow two fingers to fit comfortably underneath the straps.

• Avoid rubbing behind the elbows or restricting movement.

• Be adjusted so it doesn't twist or slide around the body.

When combined with reward based training, a Y-shaped harness allows us to teach loose lead walking through positive reinforcement, engagement, environmental rewards and clear communication, rather than through pressure around the neck.

As with any piece of equipment, fit matters. An ill fitting harness can restrict gait and movement, so choosing the right style and ensuring it fits your individual dog is just as important as the training itself (Lafuente et al., 2018).

My Thoughts

Finding Google's AI answer genuinely shocked me.

As professionals, we should always be asking questions, reading new research and being prepared to change our opinions when the evidence tells us to. Dog training is constantly evolving, and thankfully so is our understanding of animal welfare.

Just because something has always been done a certain way does not mean it is the best way.

My goal isn't to tell people what they can and can't use. It's to encourage owners to understand how equipment works, what their dog is learning from it, and whether there's a kinder way to achieve the same outcome.

For me, that means choosing equipment that prioritises welfare while teaching dogs the skills they need to succeed. A well fitted Y-shaped harness, paired with reward based training, allows dogs to learn without unnecessary pressure on one of the most vulnerable parts of their body.

Equipment doesn't teach dogs.

We do.

And how we choose to teach matters.

References

Lafuente, M. P., Provis, L., & Schmalz, E. A. (2018). Effects of restrictive and non-restrictive harnesses on shoulder extension in walking and trotting dogs. Veterinary Record, 182(15), 426.

Pauli, A. M., Bentley, E., Diehl, K. A., & Miller, P. E. (2006). Effects of the application of neck pressure by a collar or harness on intraocular pressure in dogs. Journal of the American Animal Hospital Association, 42(3), 207 to 211.

Skinner, B. F. (1938). The Behavior of Organisms. Appleton Century.

Vieira de Castro, A. C., Barrett, J., de Sousa, L., & Olsson, I. A. S. (2020). Carrots versus sticks: The relationship between training methods and dog owner attachment and dog behaviour. Applied Animal Behaviour Science, 225, 104945.

Ziv, G. (2017). The effects of using aversive training methods in dogs. A review. Journal of Veterinary Behavior, 19, 50 to 60.