Find a Security Clearance Job!


Chapter 1



Corps are the largest tactical units in the US Army. They are the instruments by which higher echelons of command conduct operations at the operational level. Higher headquarters tailor corps for the theater and the mission for which they are deployed. They contain organic combat, CS, and CSS capabilities to sustain operations for a considerable period (when employed as part of a larger ground force).

Corps may be assigned divisions of any type the theater and the mission requires. They possess support commands and are assigned combat and CS organizations based on their needs for a specific operation.

Separate infantry brigades, ACRs, field artillery brigades (FAB), engineer brigades, air defense artillery (ADA) brigades, and aviation brigades are the nondivision combat units commonly available to the corps to weight its main effort and to perform special combat functions. Signal brigades, military intelligence (MI) brigades, military police (MP) brigades, civil affairs (CA) brigades, chemical brigades, and psychological operations (PSYOP) battalions are the combat support organizations commonly available to the corps.

Other special operations forces (SOF) may support corps combat operations as necessary. The corps CSS organizations are the personnel group, the finance group, and the corps support command (COSCOM).

Future corps operations will possess several key characteristics. Operations will be joint and, often, multinational in nature. They will reflect a need for tailored forces employed in force-projection operations, likely in response to short-notice crisis situations. They will be conducted across the full range of military operations from war to operations other than war (OOTW).

There may be times when the corps must provide resources to support operations that do not otherwise involve corps headquarters. The corps then acts as a force-provider. The corps may at times have considerable assets committed to other commands to support major and lesser regional contingencies around the world.

The corps retains significant responsibilities as the parent organization for these deploying forces while these forces are under the operational control (OPCON) or tactical control (TACON) of another commander. The organization of the corps has evolved to reflect these characteristics.

During World War II, the corps served almost exclusively as a tactical headquarters giving the field army great latitude in shifting divisions to rapidly concentrate combat power. During the Cold War, the corps' responsibilities expanded to include logistics and administrative support to subordinate units. The corps was still primarily a tactical headquarters charged with synchronizing combat operations in support of operational objectives.

Today's corps will most likely find itself conducting force-projection operations as part of a tailored joint force. When the mission calls for a preponderance of land power, the corps may perform duties as a joint task force (JTF) headquarters.

Corps operations are habitually combined arms operations. The corps possesses the organic capability to synchronize these activities across all of the battlefield functional areas. As such, corps are uniquely suited to be Army Forces (ARFOR) headquarters or the joint force land component commander's (JFLCC) headquarters of the joint task force.



The Corps as Part of a Larger Ground Force

The Corps as a JTF Headquarters

The Corps as the ARFOR or JFLCC Headquarters


Corps Headquarters

Corps Units


US Air Force

US Navy

US Marine Corps

Special Operations (SO)

Corps usually link the operational and tactical levels of war. They may link operational and strategic levels of war as well. As such, they have the key role of translating the broad strategic and operational objectives of higher echelons into specific and detailed tactics to achieve those objectives.

Corps plan and conduct major operations and battles. They synchronize tactical operations including maneuver, fires of organic artillery, naval fires, supporting tactical air, and actions of their CS and CSS units. Doing so brings together the effects of these separate activities throughout the depth of the battlefield.

Corps also act as the force provider for other headquarters tasked to control an operation. Whether the corps is the supporting or the supported command, it should receive mission-type orders.

Today's corps is the central point on the battlefield where the commander synchronizes combat power to achieve tactical and operational advantage over the enemy. Critical corps roles include--

  • Planning and conducting operations with other elements of the joint force to achieve campaign objectives.
  • Integrating available Air Force (AF), Navy, and Marine combat, CS, and CSS units, along with interagency support in land operations, including joint efforts in intelligence, target acquisition, target attack, electronic warfare (EW), suppression of enemy air defenses (SEAD), and CSS.
  • Collecting intelligence, anticipating enemy activities and intentions, and planning future actions.
  • Planning and conducting simultaneous operations in depth.
  • Nominating targets for nuclear weapons employment in support of campaign objectives.
  • Planning and conducting effective deception operations-according to the higher echelon ; s deception plan.

Operational planning concentrates on the design of campaigns and major operations. Campaign plans set broad, long-term goals, such as control of a geographic area, reestablishment of political boundaries, or defeat of an enemy force in the theater.

The corps accomplishes its goals in phases in most cases. Thus, the campaign plan normally provides a general concept of operations for the entire campaign (lasting weeks or even months) and a specific plan for only the first phase of the campaign. Major operations are the coordinated elements of a campaign. The outcome of a major operation will decisively impact the conduct of a particular phase of the campaign.

Tactical operations include battles and engagements as parts of campaigns and major operations. Divisions, brigades, and smaller units may fight engagements either as part of a battle or as separate actions. Battles are larger than engagements and may involve numerous engagements over a large area that take days to resolve.

Planning and executing tactical-level battles is a major role of the corps. The corps commander must clearly understand the intent of the commanders above him. Doing so will help him plan and execute battles that will achieve operational objectives. The corps must simultaneously conduct close, deep, and rear operations as well as plan for future operations.

When conducting simultaneous operations, the corps must synchronize one or several collateral operations with the main effort. Collateral operations consist of major activities within the scope of any combat operation. Examples of possible collateral operations are intelligence, counterfires, deep/joint fires, special operations, joint suppression of enemy air defenses (J-SEAD), humanitarian assistance, and deception. These operations may draw on the same resources and normally require special planning, synchronization, and unity of command and control.

A single organization under corps control usually plans and executes these operations. They may be operations for which the corps is either best suited to control or for which the corps should assume responsibility because of the specific situation.

There are several reasons why the corps may want to assume this responsibility. The collateral operation may involve coordinating joint functions, employing scarce resources, focusing on attainment of critical objectives, or allowing subordinate maneuver units to focus on other operations.

The commander assigns collateral operations as specific tasks in the operation order (OPORD) keyed to the overall concept of operations. Although collateral operations require their own internal concept of operations, their concepts must be consistent with the corps commander's overall concept of operations.

A corps headquarters may function as the Army service headquarters of a subordinate joint force, the JFLCC headquarters of a JTF, or as the JTF headquarters itself. In such cases, the corps is responsible for both operational and tactical planning and operational and tactical execution of the campaign. The centerpiece of the corps' operational responsibilities is participation in the development of a supporting joint campaign plan. (See Joint Publication (JP) 5-00.1 for a detailed discussion.)

By its nature, the corps will always fight as part of a joint force, working closely with its sister services. The nature of current world politics, in addition to US treaty commitments, means the corps may fight as part of a multinational force. The implications of these joint and combined operations are no different from those FM 100-5 and FM 100-7 discuss, but are of particular significance to the corps.

The Corps as Part of a Larger Ground Force

The corps may be located in or deployed to a theater to fight as a component of a larger ground force. This situation occurs when a significant military threat exists in a specific geographic region or because of treaty obligations.

Currently, V Corps is forward-deployed in Europe, and I Corps is Continental United States (CONUS)-based, yet under the Combatant Command of the US Pacific Command (PACOM). Under these conditions, the corps normally operates as part of a multinational force and is under the control of a multinational command structure.

Coalition forces usually have specific areas of operations (AOs) and missions that should be relatively well-defined even before the outbreak of war in their theater. Such corps may have the advantage of having a larger logistic base composed of a combination of US and host-nation (HN) resources. The corps may be required to provide logistic support to other US forces or allies.

While major subordinate elements normally locate with a forward-deployed corps, there may still be some deployment of CONUS-based forces to support the corps. The time-phased deployment of these augmentation forces is of major concern and must be well-integrated into both tactical and sustainment planning.

Corps with missions to respond to worldwide situations frequently fight as the largest ground formation in the theater, possibly with the corps commander serving as the JTF commander. These corps plan for employment in theaters of likely hostilities.

The threat, which corps will encounter, is often poorly defined. Enemy forces may range from irregulars to mechanized forces with a high degree of technological sophistication to forces that are asymmetrically modernized.

Corps are capable of deploying anywhere in the world. For this reason, they must consider employment of light, special operations, and armored maneuver forces, capable of both rapid deployment and the ability to conduct operations in a variety of situations. Corps may require augmentation of selected CSS forces to perform sustainment operations.

The Corps as a JTF Headquarters

A joint task force is composed of Army, Navy, Marine Corps, and Air Force assigned or attached elements or two or more of these services. It is constituted and so designated by the Secretary of Defense, by a combatant commander, or by the commander of a subordinate unified (subunified) command or an existing JTF. (See JP 1-02.) Normally, a JTF is established for a specific purpose or task. Usually the task is limited in scope and duration and there is little need for centralized control of logistics.

The corps commander, as the commander, JTF (CJTF), is subordinate to the establishing authority and must look to him for guidance, strategic direction, and missions for the joint force. In turn, the CJTF exercises OPCON or TACON of assigned forces.

The CJTF also forms a joint staff and establishes joint boards and centers, as necessary, to command and control the force. This ensures that the staff is representative of the joint force, and it provides a structure for planning and executing joint operations.

The corps may require augmentation to transition to this joint staff structure. Augmentation maybe in the form of a deployable joint cell to provide initial assistance or a major augmentation of personnel and equipment based on the JTF's size and composition.

The establishing authority is responsible for providing augmentation to the JTF. However, the corps commander, as the CJTF, must make his augmentation requirements known. (Chapter 4 contains details of corps augmentation for JTF operations.)

The corps as a JTF can conduct either tactical-or operational-level operations. The mission, not the size of the force, determines at which level the JTF functions. When the focus is on conducting joint operations to attain theater-strategic objectives, the JTF serves as an operational headquarters. However, the commander must fully understand both the tactical and operational-level environments to ensure a supportive relationship exists between his plans and operations and those of subordinate and higher headquarters.

The CJTF takes guidance from the establishing authority and assigns objectives and tasks for the various components of the force. If planners have not developed a supporting campaign plan, the JTF may have to produce one.

In any case, as an operational-level commander, the CJTF must identify the conditions the force needs to attain strategic goals (ends). He must also detail the sequence of activities, from deployment or mobilization through redeployment or demobilization (ways), that will achieve those conditions. Finally, he must identify the resources (means) the force will need to apply to the effort.

Although the commander applies the military element of power, he also considers those interagency, political, economic, informational, and other resources that may be available and appropriate for the task at hand. The CJTF must understand the strategic and regional environment, including US policies, treaty commitments, status of forces agreements (SOFA), coalition parties' interests, and so on.

These influences affect campaign and operational planning and the establishment of rules of engagement (ROE) for the joint force. While conducting operational-level planning, the JTF synchronizes the activities of land, air, maritime, special operations forces, space, and combined forces toward military objectives that achieve the strategic end state.

Planners must include political, economic, informational, and interagency considerations in the planning process and synchronize the execution of operations. Joint task force campaign plans must sequence these activities to achieve strategic objectives.

The Corps as the ARFOR or JFLCC Headquarters

The CJTF establishes the organizational structure of the JTF and exercises OPCON of all assigned and attached forces. Joint Publication 5-00.2 outlines specific guidance for options for conducting JTF operations.

One option for organizing a JTF and exercising OPCON is by creating service component commands. As the name implies, a JTF-level service component command generally consists of forces from only one service that are assigned or attached to a JTF. When a corps is placed under the OPCON of a JTF, the CJTF may designate the corps as the ARFOR headquarters giving it Title 10, Posse Comitatus Act, responsibilities and, in most cases, OPCON of a number of assigned or attached forces.

When designated as the commander, ARFOR (COMARFOR), or the JFLCC, the corps has the following additional responsibilities:

  • Coordinating with other JTF-level component or functional commands.
  • Coordinating with the service component command headquarters of the JTF establishing authority for administrative and logistic support.
  • Planning and conducting operations in compliance with CJTF guidance and detailed plans.
  • Providing liaison personnel to CJTF, other component commanders, and supporting commanders, as necessary or as directed by the CJTF.

Corps are uniquely suited to be the ARFOR or JFLCC headquarters in a JTF. They are optimized for executing battle command functions the higher headquarters of ground maneuver forces requires. They can coordinate sustainment activities for significant numbers of assigned or attached forces.

Corps can also perform joint and multinational force coordination and liaison. In most cases, a corps headquarters can be the ARFOUR or JFLCC headquarters in a JTF without significant personnel augmentation.

With the exception of small operations of limited scope and duration, the corps headquarters cannot simultaneously function as the JTF headquarters and the ARFOR headquarters. If ARFOR requirements are relatively small, the corps headquarters may function in both capacities. Operations Just Cause and Restore Hope are recent examples of a single headquarters performing both functions.


The corps consists of a headquarters and a mix of combat, CS, and CSS units. The headquarters plans, directs, controls, and coordinates corps operations while employing its unit to accomplish its missions.

Corps Headquarters

The corps headquarters consists of the corps commander, the deputy corps commander, and the corps staff, including liaison elements assigned to work with the corps. The corps commander--

  • Interprets and translates his superior commanders' intents into his own intent and concept of operations.
  • Derives the corps' mission.
  • Provides planning guidance to focus the work of the staff.
  • Sets objectives.
  • States his intent.
  • Determines the concept of operations.
  • Assigns missions to subordinate units.
  • Designates the main effort.
  • Task-organizes the corps for combat.
  • Influences the battle by assigning missions.
  • Establishes priorities.
  • Assigns areas of operations.
  • Allocates resources.
  • Synchronizes operations within his battle space.

His intentions and objectives guide the actions of his subordinate commanders and the corps staff during operations.

The deputy corps commander extends the corps commander's span of control in areas and functions the commander designates and that mission, enemy, terrain, troops, and time available (METT-T) factors require. The deputy commander's specific duties vary from one corps to another as well as over time. However, he is normally responsible for monitoring or controlling several functions critically important to the corps operation's success. Typical duties include being the rear operations commander or controlling a specific aspect of the close operation.

The corps staff consists of coordinating and special staffs, under the control of the chief of staff (CofS), and the personal staff, which reports directly to the corps commander. Liaison elements from outside organizations work with various corps staff sections. Liaison may be provided to, provided by, or be reciprocal with the following:

  • Subordinate units.
  • The US Air Force (USAF).
  • The US Marine Corps (USMC).
  • The US Navy (USN).
  • Special operations forces.
  • Echelons above corps.
  • The battlefield coordination element (BCE).
  • Allied or coalition forces.
  • Host nations.
  • Government agencies.
  • Nongovernment agencies.

The chief of staff supervises all activities of the coordinating and special staffs in compliance with the corps commander's intent. The corps staff provides the commander with accurate and timely information, prepares analyses and estimates, and recommends courses of action (COA).

Once the corps commander decides what is to be done, the staff translates the commander's decisions and intent into instructions and orders, issues the orders, and ensures the execution of those orders. The staff must anticipate future developments and requirements as much as possible to ensure that the corps retains the tactical initiative. Field Manual 101-5 (D) discusses specific responsibilities of coordinating, special, and personal staffs.

There are several key aspects of corps staff activities that are different from lower echelons. First, because of the increased interface with multinational forces, HN agencies, and sister services, there are large numbers of liaison elements from these agencies working at the corps; their coordination with the corps staff is of great importance.

Second, the coordination of USAF, USMC, USN, and SOF support is especially critical at the corps level. The corps staff must be sure they gain maximum benefit by fully integrating available close air support (CAS), air interdiction (AI), tactical air reconnaissance and aerial battlefield surveillance (TARABS), EW, counter air operations, tactical airlift, naval gunfire, air and missile support, and sea lift into the operation.

Third, the corps must continuously plan into the future to anticipate battlefield conditions and then move forces and assemble resources in time to successfully fight the enemy. To plan continuously, the staff must anticipate conditions that may exist several days ahead. Figure 1-1 depicts a typical corps staff organization.

Corps Units

There is no standard corps organizational structure. Figure 1-2 shows a typical corps organization. Most corps will have a similar structure, although the specific number, size, and types of units will vary.


Divisions are standard combined arms organizations that commanders may tailor according to METT-T conditions. Divisions can perform any tactical mission and are largely self-sustaining. They are the basic maneuver units at the tactical level and perform major corps tactical operations. They occasionally function as operational-level headquarters, but can conduct sustained battles and engagements and OOTW.

A corps normally has from two to five divisions of any type and combination. Light infantry, armored, mechanized infantry, airborne, and air assault (AASLT) divisions are all at present in the US force structure. Each type of division has unique capabilities and limitations. (See FM 71-100 for further discussion.)

Light Infantry Divisions. Light infantry divisions add an important dimension to the strategic mobility of Army forces. Their rapid strategic deployability enable them to arrive in a crisis area before a conflict begins. On short notice, they can rapidly reinforce forward-deployed US forces. They are also available for worldwide contingencies, including in regions that lack a developed support infrastructure.

Light infantry division operations are flexible in both tactical deployment and organization for combat, but are limited in tactical mobility unless augmented. Light forces habitually operate as combined arms teams with organic engineers, artillery, aviation, and air defense. When suitably augmented and task-organized for the mission, they are capable of executing brigade, battalion, and company-size operations. They can also be reinforced with, or can themselves reinforce airborne, air assault, special operations, armored, or mechanized forces.

Armored and Mechanized Infantry Divisions. Armored and mechanized divisions are mobile, ground-gaining forces with significant armor-protected firepower. They operate most effectively in terrain where they can move quickly and use long-range, direct-fire weapons to their best advantage. They seek to rapidly concentrate combat power against the enemy on the mobile battlefield.

Armored and mechanized divisions are somewhat limited in exploiting their mobility in restrictive terrain, such as cities, mountains, and heavily forested areas. While all force-projection operations require use of strategic-lift assets, the deployment of armored and mechanized divisions may require more careful planning in order to achieve desired arrival sequences.

Airborne Division. The airborne division can rapidly deploy anywhere in the world to establish US presence and to seize and secure vital objectives. The division conducts vertical assaults by airdrops in the enemy's rear to secure key terrain or to interdict the enemy's routes of resupply or withdrawal, The division must depend on the USAF for airlift, CAS, and aerial resupply.

Once on the ground, the division is essentially a dismounted force with limited wheeled and rotary-wing mobility. The airborne division can be used in a developed theater, especially to add depth to the offense and defense. It is particularly well-suited for force-projection operations and can rapidly deploy in situations calling for early presence buildup of combat forces.

Air Assault Division. The AASLT division conducts rapid-tempo tactical operations over extended ranges. It combines strategic and operational mobility with an extremely high degree of tactical mobility within its AO.

The AASLT division can fight by projecting significant combat power by transporting infantry, field artillery (FA), and other combat and CSS units using organic helicopter assets. It can also rapidly concentrate, disperse, and redeploy its forces, making it a highly responsive mobile force.

Aviation is the prime mover, and aircraft are integrated with ground forces. In addition, AASLT operations generally involve insertions and extractions under hostile conditions, as opposed to mere air movement of troops to and from secure locations about the battlefield. The division normally relies on air or sea lift for strategic mobility but does possess a capability to self-deploy its organic multiengined aircraft to locations in Central and South America and the Caribbean.

Separate Maneuver Brigades

Except for their size, separate armored, infantry, light infantry, and mechanized infantry brigades have essentially the same characteristics as their corresponding types of divisions. Separate maneuver brigades have organic cavalry, engineer, AD, FA, MI, MP, and CSS units.

Separate maneuver brigades help reinforce maneuver divisions but are capable of operating as independent units. However, they are not capable of sustained operations unless augmented. (See also FM 71-3 and FM 7-30.)

Armored Cavalry Regiment (ACR)

The ACR performs reconnaissance, security, and economy of force operations for the corps. The regiment has organic air and armored cavalry units that can operate as combined-arms teams over wide areas and serve as reconnaissance or security forces.

The regiment also has organic AD, FA, engineer, MI, chemical, and CSS units. The regiment may conduct offensive, defensive, or retrograde operations. It is capable of independent operations but lacks infantry, a force artillery headquarters, and military police. The regiment may require augmentation in these areas. (See FM 17-95 for details.)

Aviation Brigade

The corps aviation brigade provides the corps commander with a highly flexible maneuver force capable of performing a variety of combat, CS, and CSS missions across the entire range of military operations. Aviation units can rapidly maneuver to provide the decisive component of combat power throughout the depth of the battlefield during day, night, or adverse weather conditions. The aviation brigade can operate independently or, when properly augmented, become the controlling headquarters for other combined arms elements conducting ground operations.

The corps aviation brigade consists of an attack regiment with three attack helicopter (AH)-64 attack battalions and an aviation group that consists of an assault battalion, a command aviation battalion, a CS aviation battalion, a medium helicopter battalion, a light utility helicopter (UH) battalion, and the air traffic services battalion.

Primary missions of the corps aviation brigade include attack; air assault; air movement; target acquisition; reconnaissance and security; air traffic services; enhanced command, control, and communications (C3); forward arming and refueling point (FARP) operations; and command and staff support. Other missions include limited casualty evacuation, combat search and rescue (CSAR), downed aircraft recovery, rear area reconnaissance and surveillance, and aerial mine delivery.

Corps Artillery

Corps artillery contains all of the field artillery cannon, guided missile, and multiple-rocket battalions not organic to maneuver units. Corps artillery may also contain target acquisition units with artillery locating radars.

The cannon artillery and missile and rocket battalions are normally field artillery brigades allocated as needed to reinforce the fires of artillery units supporting committed maneuver units. They might also remain under corps control to provide general support (GS) fires. Artillery at corps is used to add depth to the battle, to support rear operations, and to influence the battle at critical times.

Military Intelligence (MI) Brigade

The MI brigade contains operations, tactical exploitation, and aerial exploitation battalions as well as a brigade headquarters. These units conduct intelligence and electronic warfare (IEW) functions in GS of the corps. They augment the intelligence and counterintelligence (CI) capabilities of the corps' subordinate units.

The brigade collects and analyzes information from multiple sources, such as communications intercept, enemy prisoner of war (EPW) interrogation, imagery exploitation, and weather forecasts. Its collection capabilities, combined with its information links from theater and national sensors, provide the corps with the ability to "see deep" into enemy rear areas.

The operations battalion provides a support element to the corps headquarters. Sections of the battalion assist the G2 in intelligence and CI planning, management, analysis, production, and dissemination. They also assist the G3 in EW, operations security (OPSEC), and deception planning.

Engineer Brigade

The engineer brigade controls corps engineer units not organic to maneuver units. The brigade provides mobility, countermobility, survivability, topographic engineering, and general engineering support to the corps and augments engineer support of the divisions and other subordinate units.

The engineer brigade may contain combat engineer battalions, engineer battalions (combat heavy), and separate engineer companies, such as CS equipment, assault float bridge, topographic, and tactical bridge companies. Engineer groups are also found in the engineer brigade when the size of the brigade requires the use of these intermediate control headquarters.

Air Defense Artillery (ADA) Brigade

The ADA brigade contains weapons systems designed to protect the force from aerial attack, missile attack, and surveillance at all altitudes. Subordinate battalions employ a combination of missile systems supported by an identification, friend or foe (IFF), capability.

Corps AD battalions usually conduct tactical operations in support of corps priorities, but may also be tasked to reinforce division AD units. Corps AD priorities include forces, facilities, and functions crucial to the success of the corps' concept of operations.

The commander coordinates and synchronizes corps air defenses with both division defenses and those that EAC forces provide. The EAC air defense forces usually include aircraft of US and allied air forces; long-range, high-altitude missile systems of theater surface-to-air missile (SAM) units; and the supporting radar and C2 network of the theater-integrated AD organization.

Signal Brigade

The signal brigade installs, operates, and maintains voice and data communications within and between corps C2 facilities. The signal brigade also maintains an extensive area network that connects all elements of the corps.

When supporting split-base operations, the signal brigade provides communications to link corps elements at the sustaining base to corps units at intermediate staging bases and in the objective area. When the corps is the JTF or ARFOR HQ, the signal brigade installs communications links to USMC, USAF, USN, and special operations component commands.

In OOTW, the corps signal brigade provides links to HN, UN, allied forces, and government and nongovernment agencies, as required. In disaster relief operations, the corps signal brigade may assist in restoring critical civilian communications.

Theater tactical communications assets normally deploy in support of each corps JTF or air component commander (ACC) to augment the corps signal brigade. These assets provide range extensions and automatic switching, and they support EAC, CS, and CSS units. The corps signal brigade terminates communications links from theater tactical networks.

Chemical Brigade

The chemical brigade commands, controls, and coordinates CS operations of attached chemical units. It also provides command and administrative and logistic support to attached chemical battalions. The brigade commander recommends nuclear, biological, and chemical (NBC) mission priorities to the corps commander. The brigade provides smoke generator; NBC reconnaissance; and NBC decontamination support (less patient decontamination) in the corps area.

Brigade chemical battalions support corps units in specified command or support relationships. The brigade also evaluates and determines corps decontamination, NBC reconnaissance, and smoke requirements.

Military Police (MP) Brigade

The MP brigade usually has from three to six MP battalions and provides battlefield circulation control (BCC), area security, EPW and civilian internee operations, and law-and-order support to the corps. It conducts reconnaissance and surveillance, to ensure security of main supply routes (MSR), and area reconnaissance of other key areas in the corps' rear.

In support of rear operations, this brigade normally provides the initial Level II response force to counter threats that exceed base and base cluster defense capabilities. It can assist tactical combat forces in Level III responses. This brigade can be designated as a tactical combat force for Level III threats, operating independently or augmented according to METT-T.

The MP brigade augments the organic MPs of committed maneuver units as required. The corps MP brigade with USAF elements may conduct joint operations during air base defense activities.

The brigade maintains close liaison with HN civil and military police and often provides civil-military operations (CMO) support. Joint and multinational operations with HN civil and military police might occur during MP brigade missions.

Civil Affairs (CA) Brigade

The CA brigade, in support of the corps, normally consists of a brigade headquarters and headquarters company (HHC) and from three to five CA battalions. Under the corps G5's supervision, the brigade headquarters analyzes the corps' mission for CA requirements, prepares the CA annex to corps plans and orders, and establishes liaison with joint service and other CA organizations.

The brigade headquarters company contains four technical support teams. Each team contains government, economics, public facilities, and special functions sections. These sections provide CA technical advice and assistance to unit commanders throughout the corps area.

A CA battalion is normally attached to each division and the COSCOM. Under the staff supervision of the division G5 or the COSCOM CMO officer, the battalion plans, coordinates, and supervises CA activities as directed.

Psychological Operations (PSYOP) Tactical Support Battalion

Corps PSYOP support normally consists of a PSYOP tactical support battalion with from one to three PSYOP tactical support companies. The battalion provides the corps with a corps PSYOP support element (CPSE). This element provides interface with a PSYOP task force (POTF) or a joint PSYOP task force (JPTOF).

Each tactical support company normally is in direct support (DS) of a division, separate brigade, or ACR. Tactical support companies provide product development and tactical dissemination.

Corps Support Command (COSCOM)

COSCOM is the corps' principal logistic organization. It provides supply, field services, transportation (mode operations and movement control), maintenance, and combat health support (CHS) to the divisions and to nondivision corps units. The COSCOM is not a fixed organization and contains a mix of subordinate units as required by the corps' size and configuration.

Within the COSCOM are functional control centers; a materiel management center (MMC); the movement control center (MCC); a medical brigade; a transportation group (when three or more functional transportation battalions are assigned); and corps support groups. These elements provide supply (less Class VIII), maintenance, and medical transportation and services to division and nondivision units.

Sustaining forces in any major regional contingency (MRC) or lesser regional contingency (LRC) requires the mobilization of selected reserve component (RC) units and personnel. Commanders can organize these mixed active and RC packages into modules tailored to the overall composition of the force. (See Chapter 3 for details.)

Finance Group

The finance group commands, controls, and coordinates the finance operations of all corps finance battalions. It provides administrative and logistic support to assigned finance battalions. The finance group normally has from two to six finance battalions.

Finance battalions provide finance support to all corps divisional and nondivisional units. Finance support includes commercial vendor services and contracting support, military pay, disbursing, funding, accounting, travel pay, civilian pay, and non-US pay (for EPW, local hire labor, and so on).

Personnel Group (PG)

The PG mission is to sustain corps and EAC personnel readiness and to exercise C2 over personnel units. The PG manages critical personnel systems and synchronizes the corps' personnel network through the personnel management center (PMC) formed from adjutant general (AG) and personnel operations. The personnel group normally commands a headquarters detachment, personnel service battalions (PSB), replacement companies, and the corps band.

Personnel service battalions are responsible for critical tasks associated with the following systems: data base management of personnel accounting and strength reporting, casualty operations management, and personnel information management. They are also responsible for the following essential personnel services: identification document, personnel evaluations, promotions and reductions, officer procurement, and soldier actions.

The PSB exercises C2 over from two to six identical personnel detachments and a modular postal company. This modular structure enables commanders to tailor their organizations to support specific missions in accordance with METT-T.


US Air Force

The USAF's contributions to joint operations include a range of missions and capabilities that meet Department of Defense (DOD)-mandated service responsibilities and functions. Missions that most directly affect corps operations include--

  • Counter air--to gain control of the aerospace environment.
  • Air interdiction--to delay, disrupt, divert, or destroy an enemy's military potential before it can be brought to bear effectively against friendly forces.
  • Close air support--to support surface operations by attacking hostile targets near friendly surface forces.
  • Special operations--to influence the accomplishment of strategic or tactical objectives normally through low-visibility, covert, or clandestine military actions.
  • Airlift--to deploy, employ, and sustain military forces.
  • Reconnaissance and surveillance--to collect information from airborne, orbital, and surface-based sensors.

The USAF also performs specialized tasks to enhance the execution of its missions. Tasks that most often enhance corps operations include--

  • Aerial refueling--to extend the range, payload, and flexibility of air operations.
  • Electronic combat (electronic warfare performed by aerospace forces) to control selected parts of the electromagnetic spectrum in support of combat operations.
  • Warning, command, control, and communications--to provide warning and characterization of an actual or impending enemy attack, and the C2 of forces through the sustained ability to communicate with those forces.
  • Intelligence--to acquire, correlate, analyze, and apply intelligence data to provide essential information for deciding how, when, and where to engage and attack the enemy.
  • Weather service--to provide timely and accurate environmental information to support the decision process for employing forces in combat operations.
  • Medical evacuation--to provide timely aeromedical evacuation to clear corps hospital of those patients exceeding hospitalization limits.

US Navy

The USN participates in joint operations and conducts a wide range of operations and tasks. Department of Defense-mandated USN directives that most closely affect corps operations include--

  • Providing naval forces (including naval air) to conduct amphibious operations.
  • Providing sea-based air defense.
  • Providing CAS and naval support for land operations.
  • Providing sea movement of personnel and cargo through the Military Sealift Command (MSC).

During the planning phase and in the initial execution phase of amphibious operations, C2 facilities afloat are available to enhance or complement corps operations. Other Navy resources available to corps operations include--

  • Intelligence.
  • Electronic warfare.
  • Naval gunfire support.
  • Aerial reconnaissance and photography.
  • Airborne early warning.
  • Air transport.
  • Offensive and defensive air operations beyond CAS.
  • Special operations.
  • Naval construction regiment.

The joint force commander's (JFC) apportionment decision provides the basis for naval aviation support to the corps during joint land operations. The JFC may apportion excess naval aviation sorties to various missions or geographic areas to ensure unity of effort in the overall mission. The joint force air component commander (JFACC) normally plans, coordinates, and tasks these sorties.

US Marine Corps

Like the other services, the USMC conducts operations to fulfill functional areas as mandated by DOD. Operations that may complement or contribute to a corps' effort include conducting land operations essential to prosecute a naval campaign and conducting amphibious operations for which the USMC is the proponent service.

In addition to fulfilling its functional responsibilities, USMC resources may complement or enhance corps operations by providing--

  • Air and naval gunfire liaison companies (ANGLICOs) in support of US and allied divisions and subordinate elements.
  • Offensive air support, including CAS, deep air support, and airborne EW and communications countermeasures.
  • Antiair warfare to gain and maintain air superiority.
  • Assault air support.
  • Air reconnaissance.
  • Electronic warfare.
  • Airspace management within the AO.
  • Special operations.
  • Intelligence.

The USMC's tactical aviation is an organic element of each Marine Air-Ground Task Force (MAGTF). The MAGTF commander retains OPCON of MAGTF air assets during joint land operations. MAGTF air assets normally support the MAGTF. Air sorties in excess of MAGTF direct-support requirements are provided to the JFC--

  • For tasking by the JFACC.
  • For the support of other components of the joint force.
  • For the joint force as a whole.

This reapportionment and/or reallocation of USMC tactical aviation sorties occurs when the JFC determines they are required for higher priority missions and to ensure unity of effort in accomplishing the overall mission.

Special Operations (SO)

Specially organized, trained, and equipped military and paramilitary forces conduct special operations to achieve military, political, economic, or psychological objectives by generally unconventional means in hostile, denied, or politically sensitive areas. Special operations forces conduct missions throughout the full range of military operations either independently or with general purpose forces.

Special operations differ from operations by general purpose forces by--

  • Their degree of acceptable physical and political risk.
  • Their employment and operational techniques.
  • Their relative independence from friendly support.
  • Their dynamic interdependence on detailed operational intelligence and indigenous assets.

Special operations forces allow the unified or joint force commander to perform critical, relatively small-unit missions that directly strike or engage the aim or object of his operational design.

Special operations forces accomplish missions and tasks by director indirect modes of employing military power and resources. The direct mode describes applications of military power designed to coerce or force the subjugation of an adversary's will. It includes strikes and maneuvers that cause destruction, disruption, or denial of military capabilities.

The indirect mode describes applications of military resources designed to train, advise, or assist interagency activities, nations important to US interests, or surrogate forces pursuing US interests. The indirect mode of special operations encompasses engagements and economies of force that deter an adversary's use of force or that promote peace.

Special operations forces consist of four interdependent elements: special operations command and control headquarters (SOCCH), operational bases, SOF supporting units, and SOF tactical units. SOCCH integrates SO and SOF for unified or joint commanders. SOF operational bases are versatile, deployable organizations that command and control SOF tactical units for unified or joint commanders. SOF supporting units conduct relatively independent special operations. SOF tactical units are relatively small units with specialized, often unconventional, combat skills.

There are several characteristics that distinguish special operations direct and indirect employment from those of general forces. Special operations--

  • Are specific tactical operations conducted by certified small units with unique talents who directly strike or engage strategic and/or theater aims or objectives.
  • Planning begins at unified, joint, or interagency levels for SO execution requiring extensive, rigorous rehearsal, and training by small units.
  • Execution occurs within a specifically tailored C2 architecture.
  • Frequently include cover, clandestine, or low-visibility operations and may be combined with overt operations.
  • Often occur at great distances from operational bases and employ sophisticated communications systems and means of insertion, support, and extraction to penetrate and return from hostile, denied, or politically sensitive areas.
  • Occur throughout the range of military operations in war, conflict, and peacetime environments.
  • Influence the will of foreign leaders to create conditions favorable to US strategic aims or objectives.
  • Are often high-risk operations, have limited windows of execution, and require first-time success.
  • Require theater and, frequently, national-level intelligence support.
  • Often require a detailed knowledge of specific cultures and languages of a country or region.

See Chapter 4 for SO planning considerations and a more-detailed account of sister services capabilities.

Join the mailing list

Unconventional Threat podcast - Threats Foreign and Domestic: 'In Episode One of Unconventional Threat, we identify and examine a range of threats, both foreign and domestic, that are endangering the integrity of our democracy'