rT HREE hundred years ago there were fewer than 300 million people in non-Soviet Asia. Today there are 1.2 billion. Three hundred years from now, if the demographic history of the East were to parallel that of Japan or the West, there would be from four to eight billion. It is not likely that such populations will actually exist in the Asia of the future, but they would exist if the agricultural-industrial revolution of the last three centuries should continue to develop and diffuse throughout the non-Western world, with demographic consequences similar to those that accompanied the economic transformation of Europe and Japan. Asia's peoples have been increasing at perhaps three-fourths of one per cent per year; continued increases of at least this order of magnitude are inevitable in the coming decades unless political instability, the disintegration of local and regional order, economic retrogression, and the correlated famines and epidemics result in drastic increases in death rates. But indefinite continuation of growth is impossible. In the long run, the population increases created by declining mortality can lead only to greater decimations by famine and disease unless they are gradually lessened and ultimately eliminated by declining fertility. The present report is a tentative and partial assessment of the factors involved in the past and potential future growth of Asia's people, with the emphasis placed on the role of migration in the acceleration or retardation of that growth. It is unfortunate that study must be limited to the experience of those admittedly selected areas which have reasonably accurate statistics. Analysis by illustration is always dangerous, but for Asia there are no alternatives.