Field experiments are randomized experiments that take place under naturalistic conditions. This research method is experiencing rapid growth throughout the social sciences and especially in legal studies, where it is used to rigorously evaluate policies and programs. We begin by charting the growth of field experimentation in law and legal studies, describing the statistical properties of experiments and discussing the practical threats that may undermine experiments conducted in field settings. Next, we review the experimental research literature in a variety of domains: legal institutions, including the judiciary, legislature, and legal profession; incentives, especially as they apply to tax compliance and business law; and laws and obligations, including legal code, policy, and legal theory. We conclude by highlighting some of the challenges that the experimental literature must confront if it is to speak convincingly to issues of law and policy.


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