Roles in the Corps

There are hundreds of ways to serve, and every Marine trains in an area of expertise that contributes to the success of our missions.
Whatever their expertise or field of training, Marines are ready to transition from mission to mission at a moment's notice.


Marines in the Ground Ordnance Maintenance field are responsible for inspecting, repairing and maintaining the weapon systems in the Marine Corps. Marines in the Ammunition and Explosive Ordnance Disposal (EOD) field are trained to handle hazardous materials and to disarm explosives.

Initial Training

After recruit training, Marines in this field may complete a technical ordnance repair course based on their specialty, such as the Enlisted Ammunition Specialist Course in Redstone, AL, or the Light Armored Vehicle Repairman Course in Camp Pendleton, CA.

Within the MEU

Ground Ordnance and EOD Marines deploy as part of the Ground Element in support of LAV and infantry units.

Specialties in Ground Ordnance/Ammunition and EOD include:
  • Ammunition Technician: Receives, stores, issues and handles ammunition and toxic chemicals.
  • Small Arms Repairer/Technician: Inspects, maintains and repairs small arms.
  • EOD Technician: Locates, identifies, renders safe and disposes of bombs and other hazardous materials. Marines must earn the rank of Sergeant before moving into this specialty.


MAGTF refers to the unique four-part structure that organizes Marine Corps operating forces. This framework brings together Aviation, Ground and Logistics Combat elements under a central Command element. The result is a flexible, combined-arms unit with the capabilities to conduct the Marine Corps' full range of operations, from humanitarian aid and disaster relief to projection of power from the sea. 

Many Roles. One Mission.

The Marine Corps is only as capable as each and every Marine. That's why all Marines have a specific role for which they are optimally trained, in support of the overall mission.



A MEU, or Marine Expeditionary Unit, is the smallest type of MAGTF, often providing the most substantial response in the shortest amount of time. 2,200 Marines that are trained in hundreds of areas of expertise serve on a MEU. Here is the breakdown of a MEU's makeup:

Command Element – Approximately 200 Marines. Responsible for command and control of the entire MEU.

Ground Combat Element – Approximately 1,200 Marines. A Battalion Landing Team that includes three rifle companies, a weapons company, a battery of artillery and platoons of the following: combat engineers, light armored reconnaissance, tanks, Force Reconnaissance and amphibious assault vehicles.

Aviation Combat Element – Approximately 500 Marines. A MEU's ACE is built around a medium tilt-rotor squadron, reinforced by CH-53E heavy lift helicopters, light attack helicopters and Harrier attack jets. The result is a squadron of 25 to 30 aircraft.

Logistics Combat Element – Approximately 300 Marines. Provides supply, transportation, maintenance and additional support for the MEU.


MEUs deploy aboard an Amphibious Ready Group (ARG): Three naval ships specifically designed to provide the Marines with a mobile base of operations. See here what serving aboard a MEU entails.