Well, I remember going through this with my now 8 year old. She would bite babies at daycare, my friends, me, her father, the babysitter, absolutely anyone who stayed around her long enough became a target for her biting! I tried everything, ignoring the behaviour, time outs, alone in her room time, everything that I tried didn't stop her. Finally she ended up biting a very good male friend of mine on the inside of his thigh, very close to a place a man does NOT want to get bit while he was sitting on a chair and didn't see her coming and he screamed and scared the heck out of me! I realised that I couldn't let this go on any longer and tried the one thing that everyone told me NOT to do and that was to bite her back! I bit her arm and left faint teeth marks (No, I didn't break the skin)she cried and looked at me like I was torturing her, I told her that biting hurts, don't do it again, and she never did! Sometimes she would forget and go to do it to another child who was trying to take a toy and I told her again, biting hurts, don't do it! She looked at her arm and stopped immediately! I am not saying that this is the right way to go about stopping a biter but it worked when nothing else would, and I think that sometimes a child has to experience the pain they are inflicting to know that it is wrong to do it. But only in severe cases, I honestly thought I was going to have to put a muzzle on her or never take her anywhere else until she was old enough to know better! Anyway, I now have a 1 year old who likes to nip once in a while but hopefully he won't escalate into a full blown biter like my daughter! Good luck to you, and if you find another way that works please, please let me know!