This book examines our environmental problems from a global perspective. The problems are cast into their social, economic and political dimensions. Population, misuse of resources, the impact of technology, unbalanced development, and the world-wide dilemma of urbanization are explored. The authors have sought to report what is known and not known about the human environment. They point up the differences in values among individuals and nations which account for sharp disagreements as to present dangers and the means to a more harmonious balance between the natural and man-made environments. The book was prepared on commission for the United Nations, and provided a conceptual basis for the United Nations Conference on Human Environment, 1972, held in Stockholm. (JP)