These first three volumes of a promising series are strong evidence that the policy sciences of development are beginning to emerge as an identifiable problem-oriented frame of reference, intersecting every specialized field of knowledge. The goals of development are gaining clarity; the historical perspective deepens; the interdependence of conditioning factors is better understood; the probable lines of future growth are more fully projected; and the invention and evaluation of policies designed to maximize or at least to achieve minimum results are forging ahead. The editors of each volume have woven theory and data into coherent patterns, and many essays—such as the chapters by Marx, Riggs, Lerner, and Pool—are sharply centered on the hitherto underdeveloped topics with which they come to grips. The Almond-Coleman model of political development lurks meaningfully in the wings.