Combat and operational stress refers to service members' reactions to demanding military operations. This stress can surface through the condition of a service member's emotional, intellectual, physical, and/or behavioral well-being.

An operation is "a sequence of tactical actions with a common purpose or unifying theme."

Combat and operational stress control involves programs and actions taken to prevent, identify, and manage the negative impact of combat and operational stress on service members.

“An assigned military job or occupation.”

Operationalization refers to the process of using theoretical concepts to create measurements which can appropriately measure the variables of interest.

“The Special Operations Command oversees the special operations capabilities of the various military branches, coordinates their training, strategy, interoperability and operations.”

Operation Inherent Resolve (OIR) is the U.S. military campaign against the Islamic State of Iraq and Syria (ISIS), conducted by a combined joint task force. The mission began in 2014 and is still ongoing.

“The physical, cognitive, emotional, and/or behavioral stress symptoms as a result of combat or as a result of other operations; these reactions may be experienced for just a few hours or days or may persist for weeks, months, or longer.”

“Develops effective biomedical countermeasures against operational stressors and to prevent physical and psychological injuries during training and operations in order to maximize the health, readiness and performance of Service members and their Families.”

Operation New Dawn (OND) was the new name given to U.S. involvement in Iraq, previously known as Operation Iraqi Freedom (OIF), on September 1, 2010 as the role of U.S. troops was reduced in Iraq. OND was drawn to a close at the end of the Iraq War in December 2011.

Operation Enduring Freedom (OEF) was the title used by the United States to refer to the Global War on Terrorism. OEF began on October 7, 2001, in response to the September 11, 2001 terrorist attacks, after which the United States targeted al-Qaeda and the Taliban in Afghanistan. OEF in Afghanistan ended on December 28, 2014, with the completion of the U.S.-led combat operations there.

“An overarching principle that guides military leaders as they develop regulations and policies on how to address the physical, cognitive, emotional, and/or behavioral stress symptoms that service members experience as a result of combat or other military operations and to keep stress within an acceptable range; policies and programs emphasize enhancing resilience and performance through prevention and early interventions with individuals and families who experience psychological injury.”