Roman contract law was the legal infrastructure of the Mediterranean economy. The capacity to make binding agreements enforceable by courts — across the distances, time periods, and social differences that Roman commerce required — was not incidental to the empire’s economic integration. It was the mechanism by which merchants in Alexandria could do business with partners in Antioch, by which Roman investors could finance shipping voyages to India, by which a landowner in Gaul could lease his estate to a tenant with legal remedies available if either party defaulted. Without reliable contract enforcement, the commercial sophistication of the Roman economy was impossible. Roman jurists understood this, and the sophistication of their contract law reflects the sophistication of the commercial relationships it was designed to serve.