Organizations are a defining feature of the modern world, and the study of organizations (Organization Studies) has become well established in both sociology departments and professional schools, most notably business and management schools. Organization Studies has long drawn inspiration from foundational work in sociology. In particular, "classical" works in sociology have long energized organizational research, primarily by suggesting ways of making sense of the ever-accelerating pace of social change. In recent decades, however, the field has lost interest in these sociology classics. This trend reflects and reinforces an increasingly academic focus of contemporary Organization Studies. Not only does this trend weaken Organization Studies' engagement with the big social issues of our time, but it isolates the field from the broader field of the social sciences. The aim of this Handbook is to re-assert the importance of classical sociology to the future of Organization Studies. Alongside several thematic chapters, the volume includes chapters on each of nearly two dozen major European and American theorists, each of these chapter addressing: (a) the ideas and their context, (b) the impact of these ideas on the field of Organization Studies, and (c) the potential future research these ideas might inspire. The goal is not reverential exegesis, but rather to examine how the classics can energize organizational research. This wide-ranging Handbook, with contributions from leading American and European scholars, will be a vital, informative, and stimulating resource for anybody undertaking research in, teaching, or interested in learning more about Organization Studies today.