On January 1, 1952, President Harry S. Truman appointed Shepherd Commandant of the Marine Corps. During Shepherd's four years as commandant, he initiated a number of important policies that resulted in increased military proficiency for the Marine Corps, one of the first and widest reaching of which was the institution of a General Staff System. Shepherd presented the Marine Corps War Memorial to the American people at the dedication of the memorial on November 10, 1954, the 179th anniversary of the founding of the Marine Corps. He was the first commandant to become a member of the Joint Chiefs of Staff, and upon his retirement on January 1, 1956, he was awarded a third Distinguished Service Medal.