So there you have it, an overview of a variety of common collars and harnesses. None is perfect. They are all just tools. But some are more likely to cause problems in your pet or may just provide a less than ideal match for your needs. In case you're wondering which I prefer—ideally my dog can walk on leash with the flat collar he wears regularly. But for those dogs that tend to pull and need more work, I tend to recommend a front-attaching harness or a head collar of some sort.
One of the most common alternatives to a collar is a harness. Veterinarians routinely recommend that dogs, such as pugs with their short noses, and miniature poodles with their propensity for collapsing trachea wear harnesses. However, it's important to chose the right one. In general I avoid harnesses that hook on the back unless you want to train your dog to pull a cart or a sled. These harnesses actually help train your dog to ignore you and pull you because when you pull on the leash to try to gain some control, they direct the dog's attention away from you.