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U.S. Marine Corps Forces Reserve


U.S. Marine Corps Forces Reserve

Augment. Reinforce. Support.

2000 Opelousas Ave., New Orleans, LA 70114
Commanding Officer, Third Civil Affairs Group Colonel Sean N. Day

Col Sean N. Day is a native of Tifton, Georgia.  He entered the Naval Service in 1989 and his initial assignment was the Naval Academy Preparatory School in Newport, RI.  Col Day was commissioned in 1994 upon graduation from the United States Naval Academy. 
Command billets include multiple Rifle, Weapons and Guns Platoon Commander assignments in the 1st and 4th Marine Divisions; Officer in Charge, Force Protection Detachment, 22nd Naval Construction Regiment; Commanding Officer of Weapons Company, 2d BN, 23d Marine Regiment; Commanding Officer of 2d Battalion, 23d Marine Regiment; Commanding Officer of Task Force 2/23; and Interim Commanding Officer of 2d Civil Affairs Group.    


Other operational assignments include duty as Executive Officer of 2d Civil Affairs Group; 1st BN, 23d Marine Regiment and Bravo Battery, 1st BN, 11th Marine Regiment.  He has served as Operations Officer of 2d Civil Affairs Group; 1st BN, 23d Marine Regiment; 3d Air Naval Gunfire Liaison Company; 2d BN, 23d Marine Regiment; and Company D, Marine Security Guard Battalion (State Department).  Col Day served as the Plans Officer, Assistant Operations Officer, Air Officer and Fire Support Coordinator of the 2d BN, 23d Marine Regiment.  He served as Logistics Officer of Company D, Marine Security Guard Battalion (State Department).  Additionally, Col Day served as Aide – de – Camp to the Assistant Division Commander and the Commanding General of the 1st Marine Division (Reinforced).


Operational and combat deployments include service in Operation Southern Watch with the 15th Marine Expeditionary Unit (Special Operations Capable), Iraq with the 1st Marine Division, and Afghanistan with I and II Marine Expeditionary Forces (Forward).


Supporting establishment duty includes assignments to the Roles and Missions Coordination Office, Plans Policy and Operations, Headquarters Marine Corps and voting membership on the Marine Corps Reserve Policy Board.

Col Day’s military qualifications include Joint Qualified Officer II, Operations and Tactics Instructor (OTI), Naval Parachutist and Anti-Terrorism Instructor.
Col Day holds a Bachelor of Science degree from the United States Naval Academy where he was the two time recipient of the Naval Order of the Prize Award which recognizes the midshipman with the broadest knowledge of international relations, politics and diplomacy.  He received a Masters of Business Administration from Cornell University earning fellowships in both Finance and Leadership studies.  Col Day also holds a Masters of Strategic Studies from the United States Army War College.
Military awards include the Bronze Star, Navy Commendation Medal (gold star in lieu of second award), Combat Action Ribbon, Presidential Unit Citation as well as other personal, campaign and service awards.  He is a past recipient of the U.S. Navy League’s Holland M. Smith Award for Operational Excellence, which recognizes the Marine who has done the most to improve the tactical competence of the entire Marine Corps.   


In his civilian career, Col Day is the Finance Strategy Controller for the Business Management Group of the Intel Corporation (NASDAQ: INTC). He has previously held corporate finance and investment banking roles at MBNA Corp. and Merrill Lynch.