This book explores, from a broader perspective than existing literature, the developmental dimensions of the new South American regionalism within a changing hemispheric and world order in transformation. It analyses a set of specific debates: regionalism in the Americas then and now; social and economic development and regional integration; and organized crime, intelligence and defence. An in depth and critical reflection on the complex and heterogeneous path of regionalization taking place in South America from different perspectives and in key issues of regional development.