This chapter focuses on Sir William Blackstone (1723–1780), the author of the most important book in the history of the common law. The four-volume Commentaries on the Laws of England (1765–1769) and the series of lectures Blackstone delivered at Oxford from 1753, changed the way lawyers thought about the law. Blackstone’s Commentaries were read by more people, non-lawyers as well as lawyers, than any other English law book. Their influence is difficult to overstate, and extends into the twenty-first century. Almost as momentous was Blackstone’s influence on legal education. While gradual, the transfer of legal education from the law office and the courts to the university, which Blackstone pioneered, had an enormous impact on legal development, as law professors contributed to the formation of generations of lawyers and themselves came to play a significant role in legal development.