Several years ago we conceived the idea of a volume that would focus on the work of significant individual jurists. We drew up a list of prominent jurists and planned a book in which a chapter for each jurist would include a scholarly biography along with a translated sample of his work. We have contributed our own chapters, and twenty colleagues have joined us by contributing a chapter on a jurist they are engaged in studying. Each chapter offers new biographical material on a particular jurist, along with a new translation of selections of his work. Otherwise we did not ask the contributors to follow any particular format. Although practical considerations made it impossible to include all major jurists from each century, and to represent all schools, we hope that the combination of biography and translation in these twenty-three studies will offer a new way of looking at the development of Islamic legal thought. All references to the Encyclopedia of Islam are to the second edition unless otherwise noted. In general, we use the EI system of transliteration, except that we use j instead of dj and q instead of ?. We have not standardized translations of passages from the Qur??n. Each contributor has used the translation he or she thinks best. Otherwise, we shortened references in the notes and provided a complete bibliography at the end of the volume. We would like to thank everyone who contributed a chapter to the volume and, at Brill, we are grateful to Ingrid Heijckers-Velt and Nicolette van der Hoek, who guided the book to completion.