Sociological neo-institutionalism has its origins in American organizational sociology. It focuses on questions of institutional change and the societal handling of institutional mandates. Special attention is given to the social enforcement and embedding of prevailing beliefs in rational action. The insignia of modern rationality are traced in various areas of action. This volume introduces the fundamentals of neo-institutionalism, describes the most important empirical findings, and discusses theoretical advancements. Furthermore, in this second edition, similarities and differences to network sociology, the structural theories of Giddens and Bourdieu, as well as Luhmann's systems theory are identified.