Anne & QNS, I have one nail that used to split no matter what I did. A co-worker sold Avon and she had me try something called Nail Experts. It's like a clear polish and really does work. I still can't use nail polish on that nail (just paint the other nine LOL) and keep my nails short. I use the Nail Expert once a week and it doesn't split any more. I got this about a year ago so don't know if Avon still has it. I tried the Sally Hansen products but they didn't seem to help. This made a big difference.