This book addresses the multiple dimensions of the limited reach, or breakdown, of central authority in border regions of Arab states, and their implications for state sovereignty and modes of governance. These include the emergence of illicit networks of exchange, the rise of new nonstate actors in border regions, including paramilitary or jihadi groups, and the transformation of border areas into areas of regional conflict. Collectively, the essays in this volume address such processes, which have been observable in conflict-stricken countries such as Syria, Iraq, and Yemen, and in fragile political or economic contexts, like the ones in Lebanon, Tunisia, and Algeria, as well as in