Immigration is frequently an uneven transaction. When a scientist from India or a professor from Guatemala or a physician from the Philippines moves to the U.S., America's gain is the native land's loss. Since few American professionals head out to settle elsewhere in the world, the redistribution of talent serves only to widen the gap between the land of plenty and the lands of poverty. Worse still, the cycle tends to perpetuate itself: as more people leave their native country for the U.S., more are likely to leave, to join relatives or cash in on connections or simply follow examples. Though nothing new, the brain drain has recently seemed more than ever to be taking from the poor and giving to the rich: whereas 30 years ago most well-qualified newcomers to the U.S. arrived from Europe, now they stream in from the poorer countries of the Third World. "It is indeed paradoxical," says Dr. D.N. Misra, adviser to India's Council of Scientific and Industrial Research, "that the underdeveloped countries, which have the greatest need for scientists, engineers, managers and other professionals, are in fact losing many of their best-educated young men to the developed countries." Even among unskilled workers, the U.S. tends to attract the most enterprising-those who are adventurous enough to quit their homes and strike out for new opportunities in America.