With more than 60% new material reflecting advances in evidence-based treatments and the evolving roles of military mental health providers, the authoritative resource in the field is now in a significantly revised third edition. The volume provides research-based roadmaps for prevention and intervention with service members and veterans in diverse settings. Grounded in knowledge about stress and resilience, chapters describe best practices in treating such challenges as depression, anxiety, posttraumatic stress disorder, and substance use disorders. Also addressed are operational functions of psychologists in personnel assessment and selection, counterintelligence, and other areas.