Hero has never liked having his nails clipped at PetSmart, but the last time I took him in he was handled by someone he didn't know, and apparently got very obnoxious about it, even to the point of showing his teeth. This is a bad thing, as his nails grow fast and require cutting every month or so. So we're working on desensitizing him to having his feet messed with. I say "paw," take his paw, and poke it for a moment, then tell him good dog! good paw! in an enthusiastic voice, give him a treat, and generally make over him as if it's an amazing accomplishment. He's improving already. This dog will do anything for a treat!