Twenty-two facets of the world population problem are explored. The topics are economic, social, ecological, and political in nature and generally portray the stresses and strains associated with continued population growth in a world inhabited by four billion people. These aspects of the population problem are discussed: literacy, oceanic fisheries, natural recreation areas, pollution, inflation, environmental illnesses, hunger, housing, climate change, overgrazing, crowding, income, urbanization, deforestation, political conflict, minerals, health services, water, unemployment, endangered species, energy, and individual freedom. The authors conclude that analysis of the implications of population growth based on these indicators suggests strongly that the threat posed by uncontrolled growth deserves more attention from national and international leaders than it is presently getting. A bibliography of selected readings is included. (Author/DB)