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.

Field Artillery Officer

Field Artillery Officers lead Marines in tactics, gunnery, gun-line drills, communications, maintenance, transportation and logistics. They lead close-fire support for infantry, armored reconnaissance and tank units.

Specialized Training
  • Field Artillery Officers Basic Course
    Fort Sill, OK
    19 weeks
Within the MAGTF

Field Artillery Officers belong to the Ground Combat Element. Their first assignment is to a firing battery within an artillery battalion. With the exception of Forward Observers, Field Artillery Officers lead Artillery Units in providing gun support from "the rear". Future roles include fire support officer, fire direction officer, platoon leader and battery executive officer.

Beyond Your First Tour

After your first two-to-four-year tour, Field Artillery Officers typically go on a three-year B-Billet, such as recruiting duty, instructor duty at The Basic School or series commander at one of the Marine Corps Recruit Depots.

Before returning to your second tour, you will most likely attend one of three Professional Military Education Courses: Amphibious Warfare School and Command & Control Systems Course, the Field Artillery Captain's Career Course or Professional Artillery Refresher Training.



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.