The articles in this volume arose from the research program of the Social History of Early Christianity Group (now called the Social History of Formative Christianity and Judaism Section) of the Society of Biblical Literature. The interest in networks began with some preliminary suggestions of future avenues of research in the social history of the early Christian movement. This idea led to a session on the topic, but other papers in subsequent years have continued to pursue the issue. These studies are brought together in this volume of "Semeia" for two primary first, in order to introduce network theory and analysis; second, to show direct application of this approach to social history research on early Christianity and its Hellenistic-Roman environment. All the studies presented here are careful historical studies informed by sociological and anthropological methods. The volume has been organized as follows. The Prolegomena presents two studies by L. M. White to introduce the topic of networks. The three studies in Part II take the methods of network analysis into the historical arena in order to "map out" specific cases in detail. The three studies in Part III then attempt to show how an awareness of network theory and analysis provides new insights into the intellectual and religious environment. [From the Editor's Preface]