Colonel Mortenson was commissioned as a Marine Second Lieutenant in April 1983 and served with distinction around the world as an infantry officer. During his 29+ year career, he commanded at the infantry platoon, company, battalion, and regimental level.
He served at the Marine Corps Officer Candidate School, Quantico, VA as a platoon commander, company executive officer, and Assistant Operations Officer. He served as a platoon commander and company executive officer at Marine Barracks- Guam. He was a rifle company commander, a weapons company commander, and an operations officer in the 1st Battalion, 5th Marine Regiment. He served at Headquarters US Marine Corps as a current operations action officer, Commandant's Briefing Officer, and current-operations section head working HQMC operational issues with the Joint Staff, combatant commanders, other services, and the Marine Corps component commands.
He served as II Marine Expeditionary Force (MEF) Expeditionary Operations Officer and Deputy Current Operations officer as well as the Current Operations officer for the 2D Marine Expeditionary Brigade before assuming command of the 2d Battalion (infantry), 8th Marines (2/8) in December 2001. During his command tour with 2/8, the battalion deployed and participated in combat operations during OPERATION IRAQI FREEDOM as part of Regimental Combat Team-2, 2D Marine Expeditionary Brigade/Task Force Tarawa (Jan-Jun 2003).
                       Following his combat tour of duty, Colonel Mortenson served as the G3 Operations Officer for the 2ND Marine Division. In 2005 he assumed command of The Basic School (TBS) at Marine Corps Combat Development Command (MC CDC), Quantico, VA. After TBS, Colonel Mortenson was assigned to the Joint Staff in Washington, DC, JS, Strategic Plans and Policies, where he served as the Central Asia/South Asia Division Chief. His responsibilities included leading the Afghanistan-Pakistan strategy and plan development for the Chairman of the Joint Chiefs. His Afghanistan-Pakistan strategy development work included working closely with the Office of the Secretary of Defense, the White House, the Department of State, and Congress. From July 2009 to April 2011 Colonel Mortenson served as the Chief of Staff for the Commanding General Marine Corps Combat Development Command/Deputy Commandant for Combat Development and Integration, Quantico, VA. In his final year of service Colonel Mortenson was the Director of the United States Marine Corps Command and Staff College, Marine Corps University, Quantico, VA---a fully accredited master’s degree-granting institution.
                       Col Mortenson assumed his duties as the Director of the Illinois Fire Service Institute (IFSI), University of Illinois- Urbana/Champaign in September 2012. During his tenure as Director, Director Mortenson established and guided Institute Leadership forward on a strategic vision for IFSI that included; creating quality leadership development and decision-making training & education curriculum for the fire service, enhancing and expanding practical hands-on training, expanding life safety research, expanding on-line educational deliveries, and growing the Institute's partnerships, reach and reputation nationally and internationally. He also lectured and provided presentations nationally and internationally on leadership development, decision-making, and training. He served on the Board of Advisors for Leadership Under Fire, Inc. which has as its mission, 11 advancing discipline, survival, and leadership in the fire service II and was a consultant for Corps Leadership LLC, a leadership training and development company committed to building effective, ethical leaders in organizations. He also served on the Board of the North American Fire Training Directors, including holding the position of NAFTD Vice President from 2018-2021. Additionally, Colonel Mortenson was a member of the Illinois Terrorism Task Force and the Chair of that organization's Fire Service Committee. Due to his visionary leadership and impact on the fire service industry, IFSI officially dedicated a portion of the campus as the Mortenson Leadership Annex prior to his retirement in 2021.
                       Colonel Mortenson currently is a Founding Director of the consulting group and speakers bureau, The RPM Group. He travels the country sharing his perspective on leadership and executive principles.