Admiral Giambastiani oversees the command's mission of leading the transformation of the Armed Forces of the United States.

He also provides combat ready U.S.-based Army, Navy, Air Force and Marine Corps forces to support the military requirements of U.S. unified combatant commands around the world.

Admiral Giambastiani graduated from the U.S. Naval Academy with leadership distinction in 1970. His operational assignments include tours as a division officer and department head on attack and fleet ballistic missile submarines.

Admiral Giambastiani also commanded NR-1, the Navy's only nuclear powered deep diving ocean engineering and research submarine followed by USS Richard B. Russell (SSN 687). He also commanded Submarine Development Squadron Twelve. In addition to the seven submarines assigned, the squadron served as the tactical development agent and CNO-designated Warfare Center of Excellence for submarine doctrine and tactics. Established in 1949, Development Squadron Twelve is the oldest experimental unit of its kind in the U.S. military.

Admiral Giambastiani's shore and staff assignments include duties as an enlisted program manager on the staff of the Navy Recruiting Command Headquarters, Washington, D.C., in the early days of the all volunteer force; staff officer for the assistant chief of naval operations for undersea warfare; special assistant to the deputy director for intelligence, Central Intelligence Agency; a one- year fellowship with the Chief of Naval Operations' strategic studies group and the first director of strategy and concepts at the Naval Doctrine Command. He was selected for promotion to flag rank in December 1993.

Flag assignments include duties as the deputy chief of staff for resources, warfare requirements and assessments for the commander in chief of the U.S. Pacific Fleet and director of the submarine warfare division on the staff of the Chief of Naval Operations (CNO). Admiral Giambastiani also served as the commander of Atlantic Fleet Submarine Force; commander of Submarines Allied Command Atlantic and commander Anti-Submarine and Reconnaissance Forces Atlantic.

The Admiral has also served as the deputy chief of naval operations for resources, requirements, and assessments and the head of Admiral Vernon Clark's transition team prior to his swearing in as CNO. He most recently served as senior military assistant to Secretary of Defense Donald H. Rumsfeld.