The mission of the Marine Security Guards is to provide protection to mission personnel and prevent the compromise of national security information and equipment at designated diplomatic and consular facilities. Marine Security Guards will be prepared to execute plans for the protection of the mission and its personnel as directed by the chief of mission or principal officer through the regional security officer.
Marine Corps Embassy Security Group (MCESG) Region Commands report to the Commanding Officer of MCESG and exercise command, less operational supervision, of Marines assigned to the Marine Security Guard (MSG) detachments in their respective regions. The MCESG Region Headquarters ensure the continued training, operational readiness, personnel administration, logistical support, as well as the morale, welfare, and discipline of Marines assigned for duty to MSG detachments at designated U.S. diplomatic missions in order to support the Department of State in the protection of classified material at foreign posts.
The Commanding Officer of MCESG reports to the Commandant of the Marine Corps (CMC), exercising command, less operational supervision, of Marines assigned to MSG detachments. MCESG Headquarters is responsible for the screening, training, assignment, administration, logistical support of Marine Corps unique items, and discipline of Marines assigned to MCESG. The Commanding Officer, MCESG also commands those Marines assigned to Headquarters, MCESG, and MCESG regional headquarters, and is the Director, MSG School. MSG School provides suitability screening and formal training for selected Marines to perform duties as MSGs at foreign Service Missions.