The dog is a meandering creature by nature. Canines are prone to exploring and given the choice prefer a less linear path than us humans. Getting safely from point A to point B with your dog often necessitates the use of a leash. Given the options out there, choosing the best leash for your dog can depend on a variety of things.
A standard leash with the lead that snaps onto the collar is best for basic training and every day use. It’s most often made of leather (more expensive but harder to chew through) or nylon (less durable but waterproof and cheaper). The length is fixed averaging about 6 foot. It keeps the dog close to your side and allows for greater control when training.
Slip leads are the most rudimentary of leashes. They are typically a length of nylon with a loop handle and an adjustable slipping loop. These are most often used in clinical settings and are often seen in agility training.
Lots of pet owners opt for the retractable leash. This leash is usually up to 25 feet long and retracts into a plastic case with a handle. It allows dogs more freedom to move around and explore. However, these leashes are problematic in other ways. The distance it puts between you and your dog allows for less reaction time if a situation occurs. Running into traffic, altercations with other dogs or humans and tangling up with other leashed dogs happen easily. It allows your dog to lead you (versus you leading him or her) and is not ideal when trying to teach the dog not to pull on leash. There is also the risk of the leash snapping if the dog runs with it on. This recently happened with one of our own patients and the owner ended up trying to retrieve a very scared Pomeranian from the busy thoroughfare outside our clinic.
Ultimately it is you the owner that needs to determine what works best for you both. Your ability to control your dog be it due to their size or temperament can impact the decision you make on choosing a good leash. It may also be worth checking in with your regular veterinarian when figuring on the best choice.