Abstract: This paper contains a chapter on the general structure of the law from a forthcoming book, Foundations of Economic Analysis of Law (Harvard University Press, 2003). In this chapter, I consider basic features of the legal system, including whether the law directly constrains behavior or channels it by the threat of sanctions, and whether the law is brought into play by private legal action or involves public enforcement. I investigate the conditions under which one or another structure of law will be socially desirable, and I then discuss tort, contract, criminal law, and several other areas of law in the light of the analysis of the optimal structure of the law.