Perhaps never in the history of economic thought, and certainly not since the crash of 1929, has economic analysis lagged so far behind the demands of policy as it does at present. The elevation of economic development to the top ranks of policy issues, in under-developed and advanced countries alike, has caught professional economists more than ever unprepared to deal with the most pressing economic problem of the moment. One result of this unusually large inflationary gap between the demand for solid policy recommendations and the supply of them has been an unprecedented concentration of economists’ effort on the study of economic growth. The technical assistance programmes under the United Nations, the International Cooperation Administration, the Colombo Plan, other bilateral programmes, and the Ford Foundation have given economists opportunities for “laboratory work” on a scale never before open to them. In the universities, too, more and more economists have redirected their interests in research towards economic development.