L.W.
You could try putting a children's cd in for him to listen to while he lays in his bed - sometimes listening to quiet music may help him fall asleep on his own. You could also try putting him back in his bed after he falls asleep, then give him lots of praise in the morning for sleeping in his own big boy bed by himself all night. And let him choose a special "buddy" (stuffed animal) that "needs" him to sleep with it - make him feel that he is being important to his buddy by keeping it with him at night. The main thing is to get him to be able to fall asleep on his own. You could also try telling him that you will lay in his bed with him for just a few minutes, but then he has to stay in bed and go to sleep; remind him of any big plans you may have for the next day and tell him he needs to go to sleep so he'll be ready for the next day.