In this article the problem of the quality of life is discussed within the framework of normative political theory. In the first part I suggest four kinds of background circumstances. The notion of quality of life plays a different role in each of these, depending on the differences between problems of allocation, problems of distribution, problems of pluralism and problems of international justice. In the second part I discuss the main normative solutions to such problems and I assess the scope and limits of those solutions, concentrating in particular on the theories of utilitarianism, libertarianism and political liberalism. In conclusion I argue that a particular version of Sen's capabilities approach, centered on the distinction between moral agents and patients, may provide the most promising vehicle for incorporating the notion of quality of life within a larger theory of global justice.