I have been there! First of all, it is nothing you are doing. Some kids are just better sleeps than others. My oldest daughter was just like your little one (at 11, she still has trouble falling asleep easily, and actually doesn't need that much sleep), while my son has always slept great. My third seems to fall somewhere in between. Crying it out did not work for us either. Not only did she just get more wound up, but it made me too sad. Here are some things that worked for us. Try letting her listen to relaxing music, make sure she has a nightlight or enough light so that she's not scared, a special stuffed animal to cuddle with, etc. Don't understimate how much they can understand at this age. Tell her that everyone goes to sleep at night (mommy, daddy, the sun, the dog next door, her friends, etc.) and that she has to go to sleep so she has energy to play the next day. Promise to come check on her at regular intervals if she acts like a big girl and doesn't cry and tries to go to sleep. Keep it to a few minutes at first so she sees you will really come back and for positive reinforcement, then work up to longer intervals as she is ready. You could also try a sticker chart and give her a sticker for every night she is a "big girl," with a prize after five stickers, or whatever. This worked really well with my youngest. Finally, although this would be a last resort, you could give her Benadryl for a few nights to break the poor sleep habit, although check with your pediatrician first. Our pediatrician recommended this when my oldest daughter was about 18 months old because she was getting NO sleep. After about a week, she was sleeping through the night. Good luck and hang in there!