A profound tension exists between the opposing tendencies of preservation and innovation in rabbinic legal literature. The rabbis made tremendous attempts to safeguard traditions handed down to them from prior generations in the face of significant new challenges. At the same time, these creative religious thinkers boldly invented new practices (or altered old ones) to fit shifting circumstances, designing and utilizing a rich rhetorical vocabulary to allow such necessary innovation. Through critical examination of more than 1,000 occurrences of terms depicting legal innovation, this study maps the contours of legal change reported during the rabbinic period. The Rhetoric of Innovation examines temporal clusters of statements and actions attributed to authority figures in the Tannaitic and Amoraic periods, also reviewing the geographic distribution of these words and their divergent usages in documents edited in Roman Palestine and Babylonia. It also provides significant insight into rabbinic philosophies of legal change, through exploring the various rationales deemed acceptable within the rabbinic corpus. In this respect the book carries a relevant message for modern Jewish life in its consideration of the history of appropriate boundaries and reasons for legal change-questions that recur frequently in Jewish discourse today.