Before becoming the Director of Psychological Health for the U.S. Marine Corps in May 2015, William P. Nash was a psychiatric researcher, educator, and consultant in posttraumatic stress and moral injury prevention and treatment for DoD and the VA. While on active duty in the Navy, CAPT Nash provided far-forward psychological health services to the 1st Marine Division during the Second Battle of Fallujah, for which he was awarded a Bronze Star, and he led the development of the current Navy and Marine Corps doctrine for Combat and Operational Stress Control, including its acknowledgment of moral injury and loss as important mechanisms of psychological injury. Dr. Nash has led or collaborated on research on risk and protective factors for combat-related PTSD, new measures for early recognition of traumatic stress injuries, and new cognitive-behavioral treatments for combat-related PTSD. He holds academic appointments at the University of California, San Diego, and Virginia Commonwealth University. Dr. Nash served as a member of the Institute of Medicine’s Committee for Assessment of the Effectiveness of PTSD Treatment in DoD and the VA, and he co-chaired the recently completed Chairman of the Joint Chiefs’ High-Risk Behavior Working Group.