The psychological health of active duty service-members has been an issue of significant concern for Congress in recent years, with particular attention to the links between deployments and psychological health concerns, such as post-traumatic stress disorder (PTSD). News stories have emphasised the challenges faced by some service-members returning from deployments, but psychological health is a salient issue for the entire active duty force. Overall, mental health disorders have significant impacts on service-member health care utilisation, disability, and attrition from service. In 2011, mental disorders accounted for more hospitalisations of service-members than any other illness and more outpatient care than all illnesses except musculoskeletal injuries and routine medical care. This book will discuss the prevalence of different psychological health concerns within the Armed Forces, current mental health screening and treatments, and DOD responses. It will also provide an overview of the recommendations of key reports and studies, past congressional actions and funding, and current issues for Congress. Finally, the book discusses specific mental health issues, including PTSD, alcohol and drug use disorders, depressive disorders, traumatic brain injury, and suicide in more detail.