I just finished the survey for my fifth year in National Weight Control Registry.
You've likely all read how hard it is to maintain. This registry only enrolls people who have lost 30 pounds and kept it off a year. They are trying to figure out successful maintenance strategies. Before I started my first (and only) diet, I read their findings to find out how to lose and maintain. I did what they suggested. I'm still doing fine.
You can join!