This paper explores how the ability to commit in games affect equilibrium payoffs. More precisely, we consider two-stage games, called commitment games, in which players can commit to some of their strategies in the first stage, and play the game induced by their commitment in the second stage. We completely characterize equilibrium payoffs of commitment games. Among others, we show that the power to commit in finitely repeated games as, for instance, finitely repeated prisoner's dilemma games, can lead to efficiency even though the constituent game does not satisfy the assumptions of Benoît and Krishna [1987. Nash equilibria of finitely repeated games. Int. J. Game Theory 16, 197-204].
