Combined Joint Task Force – Operation Inherent Resolve (CJTF–OIR) is a multinational military formation established by the U.S.-led international coalition against the Islamic State with the stated aim to "degrade and destroy" the organization. Led by United States Army Central (ARCENT), it is composed of military forces and personnel from over 30 countries.

Operation Inherent Resolve (OIR) is the United States military's operational name for the international war against the Islamic State, including both a campaign in Iraq and a campaign in Syria, with a closely related campaign in Libya. Through 18 September 2018, the U.S. Army's III Armored Corps was responsible for Combined Joint Task Force – Operation Inherent Resolve (CJTF—OIR) and were replaced by the XVIII Airborne Corps. The campaign is primarily waged by American and British forces in support of local allies, most prominently the Iraqi security forces and Syrian Democratic Forces (SDF). Combat ground troops, mostly special forces, infantry, and artillery have also been deployed, especially in Iraq. Of the airstrikes, 70% have been conducted by the military of the United States, 20% by the United Kingdom and the remaining 10% being carried out by France, Turkey, Canada, the Netherlands, Denmark, Belgium, Saudi Arabia, the United Arab Emirates, Australia and Jordan.