Book excerpt: Twenty years after the fall of the Berlin Wall, the question remains ‘Do good fences still make good neighbours’? Since the Great Wall of China, the Antonine Wall, built in Scotland to support Hadrian's Wall, the Roman ‘Limes’ or the Danevirk fence, the ‘wall’ has been a constant in the protection of defined entities claiming sovereignty, East and West. But is the wall more than an historical relict for the management of borders? In recent years, the wall has been given renewed vigour in North America, particularly along the U.S.-Mexico border, and in Israel-Palestine. But the success of these new walls in the development of friendly and orderly relations between nations (or indeed, within nations) remains unclear. What role does the wall play in the development of security and insecurity? Do walls contribute to a sense of insecurity as much as they assuage fears and create a sense of security for those 'behind the line'? Exactly what kind of security is associated with border walls? This book explores the issue of how the return of the border fences and walls as a political tool may be symptomatic of a new era in border studies and international relations. Taking a multidisciplinary approach, this volume examines problems that include security issues ; the recurrence and/or decline of the wall; wall discourses ; legal approaches to the wall; the ‘wall industry’ and border technology, as well as their symbolism, role, objectives and efficiency.