Walter Yasuo Oi (July 1, 1929 – December 24, 2013) was the Elmer B.
Milliman Professor of Economics at the University of Rochester in Rochester, New York.
He was a fellow of the American Academy of Arts and Sciences, a distinguished fellow of the Society of Labor Economists, and a recipient of the Secretary of Defense Medal for Outstanding Public Service.
He is credited with providing the economic basis for a voluntary military and the annihilation of a draft.