This paper examines the concepts of desert and luck, familiar in political theory but neglected by sociologists. I argue that the idea of desert is composed of both personal performance and the degree of responsibility a person has over that performance. Distribution ought to be in accordance with the indebtedness created by the person's performance. This can be compromised by luck; that is, personal desert is undermined where lack of performance scuttles the applicability of the contributory model. This paper examines recent work, focusing on establishing desert criteria for each person's ends and life-plans, and a formula for distribution according to personal welfare.