Almost immediately, Spillman was asked to rejoin the Department of Agriculture and was again given a free hand. Among his many other activities, Spillman was asked to participate in the efforts of the 1927-1928 Survey of Indian Affairs. Spillman's role required visiting reservations across the country and reporting on their economic use and potential, particularly in relation to agriculture. The final report of the Survey was published as "The Problem of Indian Administration" (Baltimore: Johns Hopkins Press, 1928). He also served as part-time professor of commercial geography at the Foreign Service School of Georgetown University from 1922 until 1931. Spillman remained with the U.S.D.A. until his death in 1931.