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Naval Center for Combat & Operational Stress Control

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  • Headquarters

    West San Diego, CA

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  • Industry

    Public Administration

Resilience and Mental Health: U.S. Marine Corps and U.S. Navy Combat & Operational Stress Control

You have likely heard many reports about the mental health needs facing our military personnel, both during combat and when they return home. Some veterans continue to face challenges years after active duty. These needs are not new, and there are numerous approaches currently operating to support veterans. One such program, called Combat & Operational Stress Control (COSC), provides a comprehensive approach and doctrine focused on fostering the resilience of members of the U.S. Marine Corps and U.S. Navy and their families. The program has been implemented over the last few years to encourage healthier responses to the stress of military life and reintegration.

The tools of the COSC create a roadmap to help service members and their families access the appropriate level of support they require to maintain mental health and recover from various levels of distress, mental injuries, and mental illness. These tools are available to active Navy and Marine Corps personnel, their families, and retired personnel. While there are clearly many unique features of working in the armed forces, many parallels can be drawn and practices can be adopted in the civilian workforce. As the COSC doctrine is in the public domain, with proper attribution the strategies can be adapted for any workplace. It is imperative for workplace leaders to be in full support of all the components of the approach for the strategies to be successful. If the strategies are adopted fully, leaders will be equipped to recognize when their employees are in distress and to react appropriately. The following is a short summary of the COSC doctrine’s origin with a high-level review of its three primary components, which are designed to work together as a comprehensive framework for supporting resilience. The three primary components are the stress continuum model, the five core functions of a leader, and stress first aid.

Background on COSC

Captain Paul S. Hammer, MD, an early champion of COSC and director of the Defense Centers of Excellence for Psychological Health and Traumatic Brain Injury, explains that the foundation of the COSC model builds upon the military culture of strong communal support generated from being part of a unit. Communal support occurs when an organized group provides its members with resources to meet their needs as well as avoid isolation. This type of community support is a known protective factor in mental health and helps prevent or reduce an individual’s vulnerability for developing a disorder (Jennings, Bryan, Bradley, & Jobes, 2011). In fact, according to Dr. Hammer, U.S. Marine Corps unit leaders were instrumental in creating the COSC model to address challenges faced by their unit members, and for this reason, the information is oriented to their perspective.

Unit leaders are regularly called upon to keep their team healthy and “ready,” or exhibiting optimal functioning and adaptive coping. They recognized additional needs in 2005, when the third year of the Iraq War saw an increase in intense fighting (Nash, 2010). The realities of combat and long deployments, in addition to other life stressors that also occur in civilian life, were cumulatively resulting in increased acute mental health needs among their units, Dr. Hammer said. At the time, the practice was to refer those in need of help to medical personnel only, removing the unit leaders from the process and isolating the unit members from their teams. Unit leaders recognized that many team members would benefit from additional support outside of a purely medical response. They were motivated by what they observed in their teams day to day and instinctively sought to increase the role of unit cohesion and support. Leaders also recognized that unit cohesiveness, while primarily protective of mental health, can also discourage reaching out for assistance outside the group, particularly when team members are faced with the stigma that surrounds mental health issues (Jennings, Bryan, Bradley, & Jobes, 2011).

In response to these unit leaders’ concerns, a more formal review was conducted in 2007 to examine the impact of mental health and distress on military personnel and to clarify who ought to be involved in the maintenance of health. Retired Navy Psychiatrist William P. Nash, MD, the primary author of the COSC doctrine, and many colleagues gathered and synthesized a tremendous amount of information on how to actively foster resilience, prevent and respond to stress problems, and eliminate the stigma associated with getting needed help. As this model has been implemented, contextual examples based on various roles as well as family status inform the identification of where a person falls on a stress continuum and how to best intervene.

The resulting COSC Doctrine recognizes that maintenance of health or any required recovery of personnel includes roles for unit leaders, the individual, and family members, as well as medical experts as required (Nash, 2010). COSC is implemented throughout the U.S. Marine Corps and Navy through various officer trainings and is included in boot camp for enlisted members. COSC’s three components — the stress continuum model, five core functions of a leader, and stress first aid — were developed to emphasize inclusion of the following key factors taken directly from the doctrine:

  • Unit leader oriented

  • Multidisciplinary

  • Integrated throughout the organization

  • Without stigma

  • Consistent with the warrior ethos

  • Focused on wellness, prevention, and resilience

These key factors reflect the impetus for COSC as well as the aim to be comprehensive in who was involved with its creation as well as its implementation. In order for COSC to be effective, there was recognition that the COSC components must fit with the culture of the military, and that focusing on strength and recovery would facilitate the reduction of stigma and remove barriers for service members seeking help.

Stress Injury as a Bridging Concept

Combat and operational stress is now seen as a literal wound to the mind, body, and spirit.

Just like physical injuries, stress injuries are important indicators of risk—both for being unable to perform normally in some situations and for developing a mental disorder, such as PTSD, if these injuries don’t heal completely.

There are other parallels between stress injuries and physical injuries—both normally heal over time, both heal faster and more completely with appropriate acknowledgement and care, and neither are the sole fault of the individual. Although physical and stress injuries normally heal, both can leave their mark, signifying lasting change in the area of the injury. Sometimes the scars caused by physical or stress injuries become places of enhanced strength, but sometimes the opposite occurs.

— COSC Doctrine

Stress Continuum Model and Using Accessible Language

The first component of COSC is the stress continuum model. Keeping with the unit leader orientation and multidisciplinary approach, military commanders, unit leaders, and health and religious ministry advisors together created the foundational stress continuum model shown. The model illustrates how unit leaders can view team member needs based on levels of stress as indicated by the four colors zones titled Ready or Green, Reacting or Yellow, Injured or Orange, and Ill or Red. The level of a team member’s mental distress guides the unit leader’s response and referral to medical professionals, if needed, which will be described in the following sections of this article in relation to the other two components of COSC.

Fundamental to the design of the stress continuum is a diagonal line going from the unit leader’s responsibility, through individual, peer, and family responsibility, to the caregiver’s responsibility. The caregiver responsibility is filled by medical and religious ministry personnel, both during combat and noncombat operations. This diagonal line reflects the unit leader’s desire to continue their involvement in the response to and recovery from the team member’s distress. While the distressed individual may rely more on the unit leader or on medical personnel, dependent on the level of distress, the unit, peers, and family members all participate in the recovery and stay connected to facilitate the return to the Ready state. This demonstrates the approach’s commitment to unit cohesiveness and support of struggling comrades working toward recovery while remaining part of the team, even if they require additional levels of intervention outside the unit.

The upper portion of defines the four zones and the features or behaviors that can be observed at each level of stress. The titles Ready or Green, Reacting or Yellow, Injured or Orange, and Ill or Red are designed both to create accessible terms and to make a bridging concept between mental and physical health. The Green zone is the desired state, where individuals exhibit optimal functioning and adaptive coping. The COSC doctrine refers to psychological wounds as “stress injuries,” which range from typical stress reactions in the Yellow zone to Red zone stress illnesses that need intervention to prevent long-term disability.

The description of the Orange zone level of distress includes causes. These conditions constitute a significant tipping point, when it is likely referrals for medical intervention outside the unit as well as more time for recovery might be required. The model defines these causes as follows:

  • Life-threat. Due to exposure to lethal force or its aftermath in ways that exceed the individual’s capacity to cope normally at that moment, life-threatening situations provoke feelings of terror, horror, or helplessness.

  • Loss. Loss can be felt due to the death of close comrades, leaders, or other caredfor individuals or the loss of relationships, aspects of oneself, or one’s possessions by any means.

  • Inner conflict. Stress arises due to moral damage from carrying out or bearing witness to acts or failures to act that violate deeply held belief systems.

  • Wear and tear. This stress comes from the accumulated effects of smaller stressors over time, such as those from nonoperational sources or lack of sleep, rest, and restoration.

By applying parallel language from physical injuries or illness to mental injuries and illness, there is an implied parallel to recovery and return to wellness and readiness. For example, when someone breaks a leg, there is typically no stigma attached. When the individual returns to work after sufficient healing time, the person may perform more slowly on the job while rebuilding strength. In the same way, people can recover from mental injuries and mental illness.

As the stress continuum model illustrates, the level and source of intervention shifts according to the level or severity of mental injury or illness, with recognition that common difficulties and the time typically needed to work through them also vary. An individual in distress can seek help directly, be referred by peers or family members, or be required to access help through the chain of command, all with the intention of having distressed individuals recover and move left through the stress continuum from the Red, Orange, or Yellow zones back to the Green Ready state.

Five Core Functions of a Leader

The second of the three COSC components is the five core functions of a leader. COSC emphasizes that leaders build resilience in their teams by helping them prepare for, recover from, and adjust to life in the face of stress, adversity, trauma, or tragedy. The overall COSC approach with all its components is being implemented across all levels of the U.S. Marine Corp and the U.S. Navy. Officers and enlisted service members get training about these tools and have access to this model, which shows the leadership’s dedication to having the model work effectively. Medical leaders provide train-the-trainer sessions to ensure the integrity of the message. COSC training is adapted to stressors that exist for specific roles such as medics or Special Forces personnel, among others. The widespread familiarity with COSC allows those who may be distressed to seek help more readily when they need it, as there is a common understanding of the terms used to describe various levels of distress.

Through the five core functions, unit leaders employ the stress continuum to recognize and react to what they observe in their teams, for example to be aware when a member moves from the Yellow zone to the Orange zone and professional care may be appropriate. The five core functions that equip leaders to accomplish this are described below:

Strengthen: For leaders to strengthen their units, they must focus on three things — training, social cohesion, and leadership. These areas have been part of military training for many years. The inclusion of the stress continuum informs the existing training as well as adds new insights. Training itself involves some level of stress, and this is required in order to build the resilience needed in combat. The unit leader should always see strengthening in light of the whole cycle. Social cohesion includes building a trusting and supportive group, which results in unit cohesion and increases protective factors. Leadership in this model is described as inspiring a focus on the mission, instilling confidence, and providing a model of ethical and moral behavior that safeguards unit members from possible discrimination or barriers to seeking help when needed.

Mitigate: As stress is a given in life, in particular for those in military service, another key role of leaders is to continually monitor the stress levels of their teams and to mitigate the impact of stressors by encouraging team members to replenish their energy levels and readiness through sleep, rest, recreation, and spiritual renewal. This allows team members to experience Yellow level stresses but return to the Green Ready state quickly.

COSC uses a metaphor of a leaky bucket for the impact and mitigation of stress. Everyone has a bucket of resources that is continually depleted through various stressors. Each person is required to replenish these resources. Just as the body requires food to fuel the muscles, the mind and spirit require various resources to operate in a healthy manner. This mitigation needs to happen both during combat and during noncombat operations.

Identify: The ability to identify stress levels assumes monitoring by leaders who know their team and will be able to recognize changes in behavior that indicate a team member is moving from Yellow into Orange or Red levels of mental or stress injury or illness. The COSC doctrine includes decision flowcharts that provide guidance on determining response. The material from these decision flowcharts has been incorporated into training presentations.

Treat: Corresponding to the levels within the stress continuum, the level of treatment should reflect and match the severity of distress. For example, a team leader witnessing rage in a team member might ask, “Are you moving into the Orange zone?” The leader might describe the behaviors that are being observed and discuss next steps with the individual. Tools available for treating various levels of stress include self-aid or buddy aid, which is nonprofessional peer support in the Yellow to Orange zones; moving to support from unit leaders, chaplains, or others in the chain of command; then finally to definitive medical or psychological treatment as the individual moves from the Orange to the Red zone. Again, maintaining connection to peers and the unit facilitates healing at all stages of intervention.

Visit the Naval Center website for training presentations geared to specific functions. These materials note that leaders, too, need to be Ready and in the Green zone to best lead and function in their role, reinforcing the need for social cohesion and using shared language to best look out for one another.

Reintegrate: This part of the cycle is crucial to rebuilding trust and mentoring the injured service member to return to the Green Ready state. It requires continuous monitoring and removal of stigma to return the confidence of the stress-injured service member and their peers. Reintegration can take months, depending on the severity of the injury or illness and the length of time a person requires for recovery. In each case, reintegration is based on measuring and weighing the capabilities and psychological readiness of the individual to perform his or her duties — again in parallel to what would be measured with a physical injury or illness. There will be cases where individuals will not recover sufficiently to return to duty. In these cases, continued support in transitioning to other work is also within the leaders’ role. With mental and stress injuries or illnesses, it is all the more significant to communicate with a consistent attitude of respect and trust. Sufficient time is required to allow the injured individual a fair opportunity to demonstrate competence and self-confidence and to regain the respect and trust of their peers. This process leans heavily on the leaders’ skills in strengthening the unit.

Stress First Aid

The third component of COSC is stress first aid. This mechanism is used by unit leaders or team members to triage, or prioritize, the seriousness of a person’s stress level as defined in the colors and levels of the stress continuum. Stress first aid is used in combat and operational situations and has three simple aims: preserve life, prevent further harm, and promote recovery. Built using the base of psychological first aid tools created for first responders in the civilian context, COSC stress first aid was designed specifically for use in Navy and Marine Corps units and families and can be applied during military training, on the battlefield, and in offices and homes. Dependent on the triage assessment, unit leaders engage any of their five core functions of leadership, apply them within the seven levels of stress first aid, and intervene in a way that is consistent with the level of distress that exists with the team member or family member.

The stress first aid cycle represents the aim of returning to wellness and readiness and includes continuous monitoring, just as all the COSC components are intended to be applied. Continuous Aid, including check and coordinate, is the ongoing assessment of stress levels. Primary Aid, including cover and calm, is a brief process that can be used by all parties and allows time to better assess what level of intervention, if any, is required. Secondary Aid, including connect, competence, and confidence, addresses more severe levels of stress in the Orange and Red zones of injury and illness and includes reaching out to others, such as military leaders, religious ministry, or medical support personnel. Secondary Aid also indicates a longer time needed for recovery, which overlaps with information from the stress continuum.

Applying COSC to Civilian Workplaces

All workers, civilian or enlisted, face varied levels of life and occupational stressors, which likewise can lead to mental stress injury or illness. Following are a few ways to adapt and provide training on the stress continuum and other components of COSC in your workplace.

Ongoing leadership and peer support. Implementing this type of program creates a supportive environment and demonstrates that fostering mental health and resilience across an organization is a shared responsibility. A socially cohesive environment for your staff includes support from leaders across all levels of your organization to build trust and respect. While the Navy and Marine Corps have implemented the COSC model in concert with the military’s integrated system of healthcare, civilian workplaces can adapt the model through coordination among leadership, managers, human resources, employee assistance programs, occupational health, and company-sponsored medical providers, with the aim of keeping the workforce healthy and productive.

  • Employers could build a “Workplace Operational Stress Control” training component into existing training vehicles. Training adapted from the COSC model could be housed with other required manager trainings such as compliance and/or sexual harassment to equip managers to observe whether negative behavior changes are arising and to react with appropriate levels of response. A separate component could be included in training for new hires so people are knowledgeable and use shared language when seeking help or when helping peers.

  • Wide use of the strategies within an organization will facilitate familiarity and adoption of the tools. Leaders and peers can reinforce use of the language from the stress continuum in recurring staff meetings or in one-on-one supervisor check-ins with staff.

  • Consider using these tools among cross-functional teams (i.e., human resources, employee assistance programs, health promotion, and integrated disability management) for a more integrated response and a common language across all benefit areas. Ongoing reinforcement of the tools’ messages during annual health fairs or health insurance enrollment periods will also build a supportive culture.

Stress mitigation. Recognize that the positive outcomes we seek in resilient workforces and mentally healthy workplaces include mitigation of stress. Coordinate efforts with wellness or employee assistance program efforts to provide specific suggestions on how staff might replenish their resource buckets.

Removing barriers. The stress continuum and the use of color terms when discussing mental stress levels can remove stigma barriers for staff to access help when they need it and help them return to the Green zone of full productivity and engagement. Early intervention can prevent an increase in the burden of some stress injuries or illnesses.

Stay connected. When situations require that a person goes on leave, remember the role of communal support. Research suggests that keeping managers engaged with employees in seeking their return to work and reintegration can improve outcomes (Christian, 2013). Staying connected with your staff will allow for smoother reintegration upon their return.

Support our veterans. By adopting the COSC approach, you not only help your own workforce, you also equip your teams to be supportive environments for veterans who are reintegrating into civilian jobs after active duty.

The comprehensive nature of the COSC approach is supported in research that addresses the various levels of support needed in the range of human experience — prevention, early intervention, and disease and disability management. We hope that this brief summary of the approach has piqued your interest and motivates you to continue or adopt supporting practices.

Thank you to all those in our armed forces for serving to protect us and in this case for making available best practices that can be adopted in the civilian workforce.

About the Naval Center for Combat & Operational Stress Control

The Naval Center for Combat & Operational Stress Control (NCCOSC) is dedicated to the mental health and well-being of Navy and Marine Corps service members and their families.

The major focus of the center is to promote resilience and to investigate the best practices in the diagnosis and treatment of posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI). The center is a program of the U.S. Navy Bureau of Medicine and Surgery.

Last Updated: July 2013


  • Christian, J. (2013). New models for preventing needless work disability: Implications for practice, policy & research. Paper presented at NIDRR Presents event, Washington, DC.

  • Jennings, K., Bryan C., Bradley, J. C., Jobes, D. A. (2011, April). Warrior suicide: Understanding the military context. Paper presented at the annual conference of the American Association of Suicidology, Portland, OR.

  • McGraw-Hill. (2002). McGraw-Hill Concise Dictionary of Modern Medicine.

  • Nash, W. P. (2010). Combat and Operational Stress Control. Washington, DC: U.S. Navy

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