The director of the Joint Staff (DJS) is a three-star officer who assists the Joint Chiefs of Staff, a cabinet of senior military officers within the United States Armed Forces who advise the secretary of defense and the president on military matters. The director assists the chairman of the Joint Chiefs of Staff in managing the Joint Staff and with the management and organization of the staff's members. The director also chairs meetings of the Operations Deputies, a subsidiary body comprising the director and a three-star delegate from each service who preview or resolve issues before they are escalated to the four-star level of the Joint Chiefs of Staff.

The Joint Chiefs of Staff (JCS) is the body of the most senior uniformed leaders within the United States Department of Defense, which advises the president of the United States, the secretary of defense, the Homeland Security Council and the National Security Council on military matters. The composition of the Joint Chiefs of Staff is defined by statute and consists of a chairman (CJCS), a vice chairman (VJCS), the chiefs of the Army, Marine Corps, Navy, Air Force, Space Force, and the chief of the National Guard Bureau. Each of the individual service chiefs, outside their JCS obligations, works directly under the secretaries of their respective military departments, e.g. the secretary of the Army, the secretary of the Navy, and the secretary of the Air Force.