There is an urgent need to better understand the causes and consequences of obesity, and to learn what works to prevent or reduce it. The purpose of this book is to summarize the findings and insights of obesity-related research from the full range of social sciences, including anthropology, economics, government, psychology, and sociology. The first section of the book explains how each social science discipline models human behavior (in particular, diet and physical activity) and summarizes the major strains of obesity research in that discipline. The second section provides information for researchers, including a guide to publicly available social science data on obesity and an overview of the challenges to causal inference in obesity research. The third section of the book synthesizes social science research on specific causes and correlates of obesity, such as food advertising, food prices, and peers. The fourth section summarizes social science research on the consequences of obesity, such as lower wages, job absenteeism, and discrimination. The fifth and final section of the book reviews the social science literature on obesity treatment and prevention, such as food taxes, school-based interventions, and medical treatments like anti-obesity drugs and bariatric surgery. The book is designed to meet the growing need of researchers for accurate summaries of the large amount of recent studies on this topic, and will be of use for researchers in every social science discipline, bringing them up to date on the relevant research in their own discipline.