The present era of staggering scientific and technological innovations, with major changes in agriculture, manufacturing, commerce, and communications, seems to document unparalleled human achievement. Yet when we examine the long-term implications, it becomes clear that an ever-growing number of humans have threatened the delicate environmental balance that sustains life on this planet. The past century may be remembered not as a period of great progress but as one marked by unrestrained consumption and failure to come close to a sustainable use of the earth's limited natural resources. In The State of the Earth, noted historian Paul K. Conkin provides a comprehensive analysis of the many environmental hazards that humans must face in this still-young century. Our activities have threatened the survival of many plants and animals, created scarcities in cultivatable soils and water needed for irrigation, used up a large share of fossil fuels, polluted air and water, and most likely created the conditions that will lead to major climate changes. Conkin not only evaluates the challenges but recognizes the successes of concerned individuals and organizations in creating awareness and in supporting policies that will best preserve a healthy earth. The State of the Earth is an invaluable resource for those who desire a broad yet thorough and scientifically informed introduction to present environmental challenges. Even when humans possess the knowledge and the tools to cope with mounting environmental problems, they may not be willing to make the needed sacrifices. Conkin demonstrates that the issues are as much moral and political as technological.