Combat and Operational Stress Control (COSC)

Combat and operational stress reactions (COSRs) are physical, emotional, cognitive, or behavioral reactions, adverse consequences, or psychological injuries that can occur in service members following exposure to stressful or traumatic events in combat or military operations. They vary in severity due to many operational factors, such as intensity, duration, and frequency of combat exposure; leadership; communication; unit moral; and unit cohesion.

COSRs are not mental health disorders or diagnosed conditions,[ Reference 1 ] and not every service member who exhibits COSRs will go on to develop a psychological health condition. COSRs are, in fact, considered normal reactions much of the time. However, their appropriate management is important, and DoD requires that each service support psychological health and early detection and management of COSRs to preserve mission effectiveness and warfighting capabilities.

Combat and operational stress control (COSC) comprises programs developed to prevent, identify and manage adverse COSRs in units; enhance mission performance; increase individual and unit resilience; conserve fighting strength; prevent or minimize adverse effects of combat stress on members’ physical, psychological, behavioral, and social health; and return the unit or service member to duty.[ Reference 1 ]


  1. Department of Defense. (2011, November 22). Maintenance of psychological health in military operations (DoD Instruction 6490.05). Washington, DC: Author.