Timber has a prong collar. It's been a life-saver. It doesn't hurt her at all because she knows she's wearing it, and when she's wearing it she won't pull. She just pulls and chokes herself on a chocke chain -- same with a nylon collar. She pulls BIG-time with a halti until her nose is rubbed raw and her tongue is bleeding. She also knows how to get it off. If she were back living with me I could correctly train her to walk on the leash again, but my family that she's living with right now are not patient with training, so the prong collar has been a God-send.