Colonel Douglas P. Thomas was commissioned in 1984 upon graduation from the U.S. Naval Academy. Following The Basic School and the Field Artillery Officer Basic Course, he was assigned to Battery E, 2d Battalion, 11th Marines, Camp Pendleton, CA.
From 1988 to 1991, he served at the U.S. Army Field Artillery School, Fort Sill, OK as an Officer Basic Course Gunnery Instructor. Following this assignment he attended the Amphibious Warfare School, Quantico, VA.
From 1992 to 1995, he was assigned to 2d Battalion, 10th Marines, Camp Lejeune, NC serving as the Battalion Liaison Officer, Battery F Commanding Officer, and Battalion Operations Officer.
In August 1995, he reported to Programs and Resources Department, Headquarters Marines Corps as a Program Planning Coordinator in the POM Development Section.
He attended the College of Naval Command and Staff, Newport, RI, from August 1998 to June 1999. He was subsequently assigned to the Operations Division, Combined Forces Command/US Forces Korea where he served as the Amphibious Operations Officer and Crisis Action Team Executive Officer.
In June 2001, he reported to II MEF Headquarters Group for duty as Executive Officer. In January 2003, he assumed duties as Commanding Officer, 2d MEB Headquarters Group and deployed with the MEB/Task Force TARAWA in support of Operations ENDURING FREEDOM and IRAQI FREEDOM.
He transferred to 10th Marines in May 2004 for duty as the Regimental S-4 and from May 2005 to May 2006, he served as the Commanding Officer of 2d Battalion, 10th Marines.
Following battalion command, he was assigned as a Secretary of Defense Corporate Fellow with Pfizer Incorporated, New York, NY from June 2006 to June 2007.
From June 2007 to July 2009, he served as the Commanding Officer of the 10th Marine Regiment.
Colonel Thomas' personal decorations include the Legion of Merit, Bronze Star Medal, Defense Meritorious Service Medal, Meritorious Service Medal (Gold Stars in Lieu of Second and Third Awards), Navy and Marine Corps Commendation Medal, Army Commendation Medal, Joint Service Achievement Medal, Navy and Marine Corps Achievement Medal, and the Army Achievement Medal.