A ten-year research effort, conducted by the International Association for the Evaluation of Educational Achievement (IEA), explored the relative merits and failings of different national systems of education in the United States and in Western and Eastern Europe. The first section of this report deals with trends in American education as seen through European eyes. The American system is viewed as a vehicle for upward social mobility and as a means of solving or ameliorating social problems. In the second section, the theoretical framework and research strategy of the IEA are described, as well as the difficulties encountered in comparing systems of education that are widely different in function and philosophy. The way individual differences are perceived and taken into account in organizing formal education in various national systems is considered in the third section. Comparisons are made of the American model of comprehensive education for all students, the Western European model, with early transfer of selected elite students to academic secondary schools, and the Soviet unitary school that integrates all types of schools. The fourth section elaborates on comparisons between comprehensive and selective systems of education. An analysis is made of performance differences in mathematics and science students in divergent systems. An overall conclusion is reached that the American comprehensive system more effectively serves all of the talent of a nation. (JD)