In response to an increasing demand for rigorous monitoring of state accountability in meeting their human rights obligations, a growing literature on human rights measurement has emerged. Yet there are no widely used indicators or indices of human rights obligations fulfillment. This paper proposes a methodology for an index of economic and social rights fulfillment that: uses available survey-based objective, rather than subjective data; focuses on state obligations rather than solely on individual enjoyment of rights; and captures progressive realization of human rights subject to maximum available resources. Two calculation methods are proposed: the ratio approach and the achievement possibilities frontier approach. The paper identifies key conceptual and data constraints. Recognizing the complex methodological challenges, the aim of this paper is not to resolve all the difficulties, but rather to contribute to the process of building rigorous approaches to human rights measurement. The proposed index thus has recognized limitations, yet is an important first step based on available data. Our goal here is to contribute to the longer term development of a methodology for measuring economic and social rights fulfillment. The paper concludes that the proposed index provides important new information compared with other measures of economic and social rights fulfillment, but still does not capture some desired features such as the right to non-discrimination and equality, and the right to social security. The paper also outlines an agenda for longer term research and data collection that would make more complete measurement possible.