In August 1942 he was elected the first Chairman of the International Wheat Council. He was Assistant Director of the U.S. Bureau of the Budget from 1944 through 1947 in the Truman Administration. In 1947, Appleby became the Dean of the Maxwell School of Citizenship and Public Affairs of Syracuse University, where he became a noted author of works in the field of public administration.
In August 1942, Appleby was elected as the first Chairman of the International Wheat Council. From 1944 to 1947, he worked as an Assistant Director at the U.S. Bureau of the Budget during Truman's presidency. In 1947, Appleby took on the role of Dean at Syracuse University's Maxwell School of Citizenship and Public Affairs, where he became a prominent author in public administration.