Social dilemmas occur when individuals make choices that are in their own best interest but not in the interest of society as a whole. Intrapersonal dilemmas occur when people make choices that are in the best interest of themselves at the moment of choice, but not in the best interest of themselves in the long run. A number of writers have observed that we can usefully model this self-defeating behavior by treating each individual as an aggregate of selves which have (...) competing interests, like the individual selves in a population. We undertake to synthesize and extend these contributions, applying the theory of intrapersonal dilemmas to addiction and procrastination, and discuss how the concept of multiple selves can explain why people attempt to control their behavior by imposing costs or constraints on themselves in the future, and how it can also help us develop new strategies of (personal) behavior control. (shrink)