Population resources and technology, by H. S. Brown.--Can we prepare for famine? A social scientist's view, by E. J. Archer.--Mariculture, by H. H. Webber.--Biomedical aspects of population control, by W. D. McElroy.--Dimensions of the world food crisis, by H. F. Robinson.--Tropical agriculture a key to the world food crises, by H. D. Thurston.--The population crisis is here now, by W. E. Howard.--The impact of disease on wildlife populations, by C. M. Herman.--Population and panaceas, a technological perspective, by P. R. Ehrlich and J. P. Holdren.--Science, birth control, and the Roman Catholic Church, by J. J. W. Baker.--Optimum world population, by H. R. Hulett.--Plants, people, and politics, by A. W. Galston.--Federal action for population policy--what more can we do now? By R. W. Lamson.--How green is the green revolution? By W. C. Paddock.