My daughter climb out of her crib at 20 months old. My husband and I were shocked and confused on what to do. We thought about one of those tent things that go on top of the crib. But in the end we converted her bed to a toddler bed at 20 months. It was a struggle for at least six months to get her to stay in it. We just enforced strict rules. We would continue to not talk to her and place her back in bed. We always stuck with the same routine until she got it. We did this until she would tire out. There where nights I didn't get much sleep trying to get her to stay in bed. It was not fun but in the end it worked. Your child might not be as stubborn as mine is and take right to it. Each child is different. If this is what you decide to do make it fun for him. Tell him you are going to have a fun time changing beds for him because now he is a big boy. Make it his day and how important it is for him to stay in bed. Maybe even have him pick out his own toddler bedding. Just make it fun and a big deal for him. I have had friends who converted from crib to toddler bed early as well and had no trouble with there children. I have one who is hard headed and stubborn. She still is to this day and she is four. There is the other option of purchasing a tent topper for the crib. I don't remember what they are called but I believe babys r us or toys r us sells them. Maybe even target or walmart. Good luck.