The collar you choose depends on several factors, including the type of dog you have, the dog’s life stage, and how well they’re trained.
In most cases, a well-trained dog is fine with a flat collar; however, if they have a restricted airway or are one of the many flat-nosed breeds, a harness might be a better option.
If you’re struggling to leash train your dog, consider obedience classes or one-on-one sessions with a professional trainer. In most cases, these two options yield better results than using a slip collar, and they reduce the chances that your dog will experience a painful or dangerous injury.