This chapter provides an introduction to the literature on interlocking directorates and corporate networks. It first traces the historical roots of the field back to the early 20th century, when researchers on both sides of the Atlantic started expressing concern about the threat to democratic process posed by the emergent corporate form, the potential for collusion allowed by the growing practice of interlocking directorate, and the general concentration of power in the hands of large firms and banks. It then outlines the major theoretical approaches employed, that focus on the corporate network as a set of both interorganizational and interindividual relationships. Third, it summarizes the main findings on the cohesiveness of the corporate community, the hegemonic position of banks, and historical changes and longitudinal dynamics of the network. Finally, it discusses most recent debates on the globalization, the emergence of a European corporate network, and the decline and recomposition of the corporate community. Introduction: problem, methods and approaches Power structure research and social network analysis Early studies of interlocking directorates and corporate networks date from the formative era of corporate capitalism at the turn of the twentieth century, when many of the smaller firms of competitive capitalism were consolidated into the forerunners to today's giant corporations. These studies were motivated by a deep concern over the increasing potential for collusion which the corporate form brought about, which for some threatened competitive markets, but for others posed a direct threat to democratic institutions, as power was being hoarded for the benefit a minority. In the first important investigation, Otto Jeidel (1905) discovered 1350 interlocking directorates in Germany between the six biggest banks and industry. For him, the interlocks network marked "a new phase in German industrial development caused by concentration and launched by the economic crisis of 1900" (Fennema and Schijf 1978: 298). Jeidel's is precisely the diagnosis at the centre of Rudolf Hilferding's Finance Capital (1981 [1910]). In the same era, Louis D. Brandeis