These are it, the one most important thing in dog training. I always assumed they were choking and hurt the dog, well they do hurt a bit, like a mommy dog telling her pup how to behave. It doesn't take much for them to learn pack rules and know they need to respond to commands or get a little "snap." It is so necessary with kids as well, how can a small kid correct a dog that is nearly as big as them? We recently adopted a 7 mon old kelty mix, zero training, just a mess. 3 days in with this collar and she is learning fast, she is sitting, laying down (we use the foot command at the same time so they learn the visual & audible commands w/ the physical one & eventually all you need is the visual/audio), not jumping, barking less, less aggressive and more relaxed (some things take more time) and overall showing she will be a great cattle dog soon. Seriously if you have any behavioral issues to correct, you need this. I put it on my older dogs only when we're out with strangers/other dogs for "in case" and to make other people feel more secure around them. But it is rarely used for them now. Plus after awhile it does rub & irritate the skin so it's not comfortable to leave on constantly.