In the past decade, the value of so-called ideal theory has become a major point of dispute among political theorists. While critics of ideal theory accuse this approach of “idle utopianism”, its advocates fault the critics for conceding to “cynical realism”. This dissertation examines two charges against ideal theory. The demandingness charge states that ideal theory fails to acknowledge the constraints on justice set by the empirical conditions that prevail in our world, and that it therefore produces invalid principles. The uselessness charge states that ideal theory, even if it tells us what justice would require under exceptionally favorable circumstances, offers no information valuable for guiding action in the nonideal circumstances ...