H.V.
There is a book called the No Cry Sleep Solution that I really liked - it is a bit gentler than just letting them cry it out. Basically the same method but not so harsh - it just tkaes a little longer because you're easing them into the change in habit rather than changing the pattern overnight. My daughter di the same thing at 9 months and is now so much better (although she still wakes a couple times a night, she doesn't wake up screaming ot be held anymore).