Here are some basic rules to use when deciding on a leash:
Dogs who pull:
1) Collar
2) Gentle Leader (these are great!)
3) Halti (great and have extra reinforcement)
4) Sensation Harness (a harness with a front chest - clasp)
5) Choker (which I do not use)
6) Prong Collar (which I do not use)
Dogs who are nervous can use:
1) Sensation Harness
2) Gentle Leader
3) Halti
Dogs who scavenge and bite:
1) Halti
2) Gentle Leader
3) Sensation Harness ** not for scavengers, only biters
Dogs who do not pull or have any issues on the street:
1) Regular Harness
2) Step-Through Harness
3) Puppia Harness
As you can see harnesses are for dogs who do not pull. This is because the placement of the lead on the leash allows the dog to continue moving forward. If you have a dog with walking issues, try to use a leash that has more control over the head or controls the direction they are walking in, and keep in mind that chokers can really hurt dogs.