In this introduction we observe that the study of social structures and social relationships constitute a common theme among the articles and commentaries contained within this special issue on Theories of Family Enterprise. Individuals and organizations are embedded in complex networks of social organization and exchange. Within business enterprises, familial relationships engender unique goals, governance structures, resources, and outcomes. We discuss these relationships, potential research directions, and the contributions made by the articles and commentaries. In so doing, we expand the literature on how social structures and social relationships affect the behavior and performance of family firms.