The view that the common law is a body of rules laid down by the courts is, for some of its proponents, implicit in the nature of the law as a system of authoritative guidance, but it has implications that are unattractive in principle and contrary to the conventional understanding of legal reasoning in the common law. Dworkin’s theory of interpretation as applied to the common law is not open to these objections, but its critics object that it lacks a sound basis in a theory of authority. In this article, I suggest an understanding of authority in the common law that explains the distinctive features of common law legal reasoning and does not equate the common law with a body of rules.