This book is the only comprehensive treatment of judicial decision-making that combines social science with a sophisticated understanding of law and legal institutions. It is designed for everyone from undergraduates to law students and graduate students. Topics include whether the identity of the judge matters in deciding a case, how different types of lawyers and litigants shape the work of judges, how judges follow or defy the decisions of higher courts, how judges bargain with one another on multi-member courts, how judges get and keep their jobs, and how the judicial branch interacts with the other branches of government and the general public. The book explains how these individual and institutional features affect who wins and loses cases, and how the law itself is changed. It is built around well-known and accessible disputes such as gay marriage, women's rights, Obamacare, and the death penalty; and it offers students a new way to think about familiar legal issues and demonstrates how legal and social-science perspectives can produce a better understanding of courts and judges.