The exclusive role of natural ecosystems is a key factor in the maintenance of the biospheric equilibrium. The current global crisis is largely caused by their dramatic decline by 43% in the past hundred years. Ignoring the immutable laws and limitations which determine the existence of all living things in the biosphere could lead humanity to an ecological catastrophe. This book presents the ecological, demographic, economic and socio-psychological manifestations of the global crisis and outlines the immutable laws and limitations which determine the existence of all living things in the biosphere. The authors are eminently qualified to write about the problems associated with the global crisis and consider the causes behind humanity's conflict with its environment. V. Danilov-Danilian, Associate of the Russian Academy of Sciences and Russia's former Minister of the Environment, and K. Losev, professor at Moscow State university, are leading Russian ecologists and I. Reyf is a journalist who specializes in ecology and global development. Dr. Danilov-Danilian works on the economics of nature management, economic and mathematical model building, sustainable development theory and ecology. Dr Losev is the chief researcher and head of the division of the VINITI. All the authors have published numerous papers, articles and books on such subjects as glaciology, hydrology, environment studies, global change and sustainable development.