Post-traumatic stress disorder (PTSD) is a serious anxiety disorder that can occur among persons exposed to traumatic events, affecting many of our nation's military and veterans. PTSD has been related to several adverse health outcomes and to increased utilization of health care services. The focus of this book is on the relationships between PTSD and chronic health conditions including other psychiatric conditions; substance abuse and dependency; chronic pain; obesity, diabetes, and the metabolic syndrome; cardiovascular disease; and traumatic brain injury.