History often reveals itself at the margins. Hegemony becomes tangible at its peripheries, claims to legitimacy are most emphatically articulated where challenged, and rules are best observed in their breach. For this reason, historians have long been drawn to the study of border zones where sovereignty was contested or subverted rather than tacitly accepted. This work by historians is complemented by, although rarely integrated with, research in other disciplines—most notably in anthropology, sociology, economics, and political science. Social scientists have been particularly interested in the question of economic organization, of how individuals and groups structure commercial exchanges in conditions of insecure property rights and unreliable recourse to official contract enforcement. Such research is frequently motivated by public policy concerns, especially the complex issue of institution-building in transition economies and so-called crisis states. While generally more circumspect about the prescriptive powers of their discipline, historians will nonetheless recognize that the defining characteristics of a contemporary crisis state—limited authority of a central government, weak institutions, ineffectual bureaucracies, widespread corruption—also apply to most, if not all pre-modern polities. Therefore, the study of actors on the fringes of political and legal regimes holds the potential to produce important theoretical insights into the construction of alternative, private-order institutions that are of significance beyond a particular period, region, or methodology.