Brigadier General O'Donohue graduated from the College of William and Mary with a Bachelor of Arts in History and was commissioned in 1984.

Command assignments include: Commanding Officer, Charlie Company, 1st Battalion, 2nd Marines (1993-1995), Commanding Officer, 2nd Battalion, 5th Marines (2002-2004), Commanding Officer, 1st Marine Regiment (2009-2010).

Staff assignments include: Ground Structure Planner, Headquarters Marine Corps (1988-1992); 8th Marines Operations Officer (1995-1996); Operations Officer, Joint Task Force Assured Response and Special Purpose Marine Air-Ground Task Force Liberia (1996); Tactics Instructor and Expeditionary Operations Program Director,  Amphibious Warfare School (1997-2000); Operations Officer, 1st Marine Division (2001-2002); Assistant Chief of Staff G-7 / Division Combat Assessment Officer (2004); Deputy Branch Head, Secretary of the Defense's Office of Force Transformation (2005-2007); Branch Head, Ground Combat Element Branch, Plans, Policies and Operations, Headquarters Marine Corps (2007-2008); Assistant Chief of Staff G-3, 1st Marine Division (2008-2009); Director, Capabilities Development Directorate, Headquarters Marine Corps (2010-2012).

 

He is a distinguished graduate of the Amphibious Warfare School, the School of Advanced Warfighting, the National War College, and the Naval Postgraduate School. He has Masters of Science Degrees in National Security Strategy and Management.

He and his wife, Rani, have been married 28 years.