A Gentle Leader is a training harness that should never hurt your dog if used properly. The Gentle Leader is a head halter that helps you control your pooch while walking.
It stops lunging and jumping, which poorly trained dogs will exhibit when out for walks. This no-pull harness is easy to use and humane when used correctly. VCA adds that you should use a gentle continuous pull rather than a jerk to achieve the desired behavior.
Once success is achieved, training should continue in varied environments and slightly more complex tasks (e.g., teaching the dog to sit during greeting rather than jumping up).