Combat and Operational Stress Control (COSC)

For more information on common deployment stressors and deployment-related stress reactions, visit the Psychological Health Effects of Deployment page

Key Terms from DoDI 6490.05
Combat and operational stress reactions (COSR): The physical, emotional, cognitive, or behavioral reactions, adverse consequences or psychological injuries of service members who have been exposed to stressful or traumatic events in combat or military operations.

Combat and operational stress control (COSC): Programs developed and actions taken by military leadership 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 service members’ physical, psychological, behavioral, and social health; and to return the unit or service member to duty.

Stress is recognized as the expected and predictable emotional, intellectual, physical and/or behavioral reaction of service members who have been exposed to stressful events in war or stability operations.[ Reference 1 ] While not all stress is recognized as being negative, and stress does not always result in long-term problems, DoD has established requirements that each service support psychological health in military operations and early detection and management of combat and operational stress reactions (COSRs) in order to preserve mission effectiveness and warfighting capabilities and mitigate the adverse physical and psychological consequences of exposure to severe stress reactions. Across the services, building skills to prevent stress-related disorders starts early in the lifecycle of a service member’s career and includes early and ongoing health promotion and stress reduction training efforts. Defined as programs developed and actions taken by military leadership to prevent, identify and manage adverse COSRs in units, each service’s combat and operational stress control (COSC) program generally aims to:

  • Prepare service members (and families) for positive adaptations to stress reactions
  • Prevent maladaptive reactions to stress and optimize deployment performance
  • Support leadership in identifying and supporting service members with combat stress
  • Manage and treat service members who experience stress reactions or other mental health concerns

DoD and the services are still in the process of trying to better understand and measure the range of COSR reactions as well as factors for identifying when a service member might be at risk for developing more debilitating stress reactions. Not every service member who develops COSRs will go on to have difficulties, but early detection and intervention of lingering deployment-related stress difficulties can help prevent the development of later psychological health difficulties. It is important to note that each service has its own COSC approach, including training and educational requirements, personnel roles, and methods of implementation throughout the deployment cycle. Please reference information about each service’s approach to COSC for more detailed information.