https://crsreports.congress.gov
Updated November 21, 2022
Defense Primer: Department of the Army and
Army Command Structure
Overview
Article I, Section 8 of the Constitution stipulates, “The
Congress shall have power ... to raise and support Armies ...
make Rules for the Government and Regulation of the land
and naval Forces ... for calling forth the Militia to execute
the Laws of the Union, suppress Insurrections and repel
invasions.”
The Department of the Army (DA) (Figure 1) is one of
four military departments reporting to the Department of
Defense (DOD). The Army’s primary mission is to fight
and win the nation’s ground wars. The Army’s mission is
both operational and institutional and is composed of four
distinct components: the regular Active Component (AC),
the reserve components of the United States Army Reserve
(USAR), the Army National Guard (ARNG), and
Department of the Army civilians (DAC). See Table 1.
The Regular Army is the full-time, federal force of AC
soldiers.
USAR is a federal reserve force that provides specialized
units and capabilities, as well as individual soldiers when
mobilized.
ARNG is a dual-status force that normally remains under
the command of state governors and can respond to
domestic emergencies, unless its units are mobilized for a
federal mission.
DAC are federal government workers who fill a variety of
support roles.
Table 1. Army Components
Source: Defense Military Manpower Center (DMDC), Military and
Civilian Personnel by Service/Agency by State/Country as of June 30,
2022.
Note: CONUS = Continental United States and OCONUS =
Outside of the Continental United States (overseas).
Senior Leadership
The DA is led by a civilian Secretary of the Army
(SECARMY) appointed by the President with the advice
and consent of the Senate. The SECARMY reports to the
Secretary of Defense (SECDEF) and serves as civilian
oversight for the Army and Chief of Staff of the Army
(CSA). The CSA is an administrative position held by a
four-star Army general and is a statutory office (10 U.S.C.
§3033). The CSA is the chief military advisor and deputy to
the SECARMY and, by statute (10 U.S.C. §151), serves as
a member of the Joint Chiefs of Staff (JCS). The JCS is
composed of DOD’s senior uniformed leaders who advise
the President, SECDEF, and Cabinet officials on military
issues.
Operational and Institutional Missions
The operational Army—known as the Operational Force—
conducts or directly supports military operations and
consists of numbered armies, corps, divisions, brigades and
battalions. The majority of the Army is based in the
continental United States (CONUS) relying on forward-
stationed and rotational units outside the continental United
States (OCONUS) to deter potential enemies, train allies,
and defend against aggression if needed.
The institutional Army supports the operational Army by
providing the training, education, and logistics necessary
“to raise, train, equip, deploy, and ensure the readiness of
all Army forces.” Army organizations whose primary
mission is to generate and sustain the Operating Forces,
such as the Army Training and Doctrine Command
(TRADOC) and Army Materiel Command (AMC) for
example, are part of what is known as the Generating Force.
Army Command Structure
There are three types of commands: Army Commands,
Army Service Components Commands (ASCCs), and
Direct Reporting Units (DRUs).
Army Commands. Army commands perform many Title
10 functions across multiple disciplines. The four Army
Commands include Army Forces Command (FORSCOM),
Army Futures Command (AFC), AMC, and TRADOC.
Army Service Components Commands (ASCCs).
ASCCs are operational organizations aligned with
combatant commands. The ASCC commander is
responsible for advising the combatant commander on the
allocation and employment of Army forces within a
combatant command. There are nine ASCCs, with five
ASCCs aligned with geographic combatant commands and
the remaining four ASCCs aligned with functional
combatant commands, including U.S. Army Cyber
