V.K.
Here is what I would try... Start by eliminating any napping in the late afternoon or early evening. This way, he is more tired at night than usual. My rule of thumb for my son is that he is not allowed to nap past 4:00 (his bedtime is 8:30). No matter how tired or cranky he may get, I always wake him up if he is still sleeping at 4:00 (unless he's sick or something of course). Put him to bed at night and if he gets up, try to limit any stimulating activity. Avoid television, playing, etc. Basically, try to keep him in bed, even if it means you have to stay there with him and rub his back, etc. I had to keep a pillow & blanket next to my son's crib for a little while. I'd lay on the floor, reach in the crib and rub his back or tummy. Once he gets used to the idea that waking up at night doesn't get him anything "fun," he'll be able to fall back to sleep on his own. If you need to, get him up earlier in the morning, so that any napping he may do is earlier in the day. It will likely take some tolerance on your part and some crankiness on his, but it will work eventually if you stick with it. Good luck!