Moral theories that demand that we do what is morally best leave no room for the supererogatory. One argument against such theories is that they fail to realize the value of autonomy: supererogatory acts allow for the exercise of autonomy because their omissions are not accompanied by any threats of sanctions, unlike obligatory ones. While this argument fails, I use the distinction it draws – between omissions of obligatory and supererogatory acts in terms of appropriate sanctions – to draw a (...) parallel with psychological perfectionism. Through this parallel, I demonstrate that requiring what is morally best is in fact counter-productive. Thus, by its own lights, a theory that wants us to do what is best ought at the very least to tell us to believe that some actions are supererogatory. As the old adage goes, the best is the enemy of the good; I argue here that the supererogatory is the solution. (shrink)