To be an expert was to assume a position of special significance in public life during and following the Progressive Era in America. To be trained in scientific principles of medicine, sociology, public administration, or economics was to be prepared to develop the opportunities and promises of American life and to reform those institutions and ideas that hindered progress. Some attention has been drawn to the limited use by government of professional academic economists starting in the early years of the twentieth century. But the work of American economists as advisers has generally been neglected, especially in relation to the study of American foreign relations. Focussing upon the work of Edwin W. Kemmerer in the five Andean countries of South America between 1923 and 1931, this article is an attempt to indicate the possibilities for fruitful research into various dimensions of foreign economic advising.