T.M.
We were able to transition our daughter at about 18 months out of our bed by converting her crib into a full size bed. We made a big deal about her having her own bed just like Mommy and Daddy. We never talked to her about the fact we wanted to sleep alone. I would lie down with her, read books, and act like I was falling sleep with her. Once she was completely asleep I would leave the room. At first she had a lot of wake ups during the night and I would go in her room and lie back down with her. Sometimes I would fall asleep for a few hours even until the next morning or I would just get up and go back to my own bed once she feel asleep.
We still lie down with her to fall asleep at bedtime (she is now 29 months) and she typically sleeps through the night until early morning. When she usually still ends up in our bed once my husband gets up for work. It was a slow transition - we worked on it for several months. But we never had a child who was scared or upset about leaving our bed.
I now have a three month old who is attached to me nursing all night. Wish me luck to transition this one in about a year! :-)