Over the last half century, economic growth has lifted hundreds of millions out of poverty and improved the lives of many more. Yet it is increasingly evident that a model of development based on economic development alone is incomplete. A society which fails to address basic human needs, equip citizens to improve their quality of life, erodes the environment, and limits opportunity for its citizens is not succeeding. Economic growth without social progress results in lack of inclusion, discontent, and social unrest. A broader and more inclusive model of development requires new metrics with which policymakers and citizens can evaluate national performance. We must move beyond simply measuring Gross Domestic Product (GDP) per capita, and make social and environmental measurement integral to national performance measurement. Tracking social and environmental performance rigorously will inform and drive improvement in policy choices and investments by all stakeholders. Measuring social progress will also help to better translate economic gains into better social and environmental performance, which will unleash even greater economic success. The Social Progress Index aims to meet this pressing need by creating a holistic and robust measurement framework for national social and environmental performance that can be used by leaders in government, business and civil society at the country level as a tool to benchmark success, improve policy, and catalyze action. Our vision is a world in which social progress sits alongside economic prosperity as the twin scorecards of success.