This publication discusses the effects of the physical environment on the maturation of children in developing nations. Part 1 examines the conceptual framework of a strategy for environmental improvement that includes the social, economic, and political underpinnings necessary for the success of such an approach. Part 2 discusses the quality of children's environments from the womb to adolescence to early adulthood, addressing various factors that adversely affect children, such as: (1) disease; (2) air, water, and ground pollution; (3) malnutrition; (4) unhealthy and unsafe housing; (5) substance abuse (by expectant mothers and older children themselves); and (6) work. Part 3 provides an overview of some programs instituted by the United Nations Children's Fund (UNICEF) to deal with the environmental problems that children and women face, and profiles of projects in the Amazon Basin, Central America, Chile, Botswana, Madagascar, Brazil, Myanmar, Sri Lanka, and Nepal. Part 4 presents conclusions about actions to be taken to improve children's environments in developing nations. (Contains 46 references.) (MDM)