This book illustrates the plethora of security concerns of the Americas in the 21st century. It presents the work of a number of prolific scholars and analysts in the continents of America. The book provides one of the only expansive applications of theory to a wide geographical area. It offers new perspectives and urges readers to take theory seriously through use. Within the Americas, we find a number of important issues that compose of this geographic security complex. Most important are the threats that supersede borders: drug trafficking, migration, health, and environment. These threats change our understanding of security and the state and region process of neutralizing or correcting these threats. This volume evaluates these threats within contemporary security discourse.