Abstract: Economists have made great progress in understanding the incentives and behavior of actors who operate outside of traditional economic markets, including voters, legislators, and bureaucrats. The incentives and behavior of judges, however, remain largely opaque. Do judges act as neutral third-party enforcers of substantive decisions made by others? Are judges "ordinary" policymakers who advance whatever outcomes they favor without any special consideration for law as such? Emerging recent scholarship has started to explore more nuanced conceptions of how law, facts, and judicial preferences may interact to influence judicial decisions. This work develops a perspective on judging that can usefully be understood as the modern manifestation of American Legal Realism, a jurisprudential movement of lawyers, judges, and law professors that flourished in the early twentieth century. The purpose of this essay is to introduce, in simplified form, the Realist account of judicial decision making; to contrast this view with alternative theories about law and judging; and to sketch out how a more explicit integration of the Realists' conceptual insights about law and judicial behavior might enrich the rapidly expanding economic work in this field.