For the first time in human history we are altering the basic physiology of the planet, yet until now there has been no single source that summarizes the medical consequences of this environmental crisis for human beings. Critical Condition provides a comprehensive, easy-to-follow review of this most critical and yet most negelected subject in the environmental debate. It brings together the best medical information available about global environmental degradation, including the effects on human health of war and military preparation, global warming, ozone depletion, species extinction, and loss of biodiversity -- matters that are generally not addressed in the literature of environmental health.Underlying these contributions are three major themes: that the habitat is an important determinant of human health, that prevention of human illness must involve protection of the environment and preservation of ecosystems, and that well-informed physicians can and should communicate with the public and policy makers about environmental hazards.Eric Chivian, Assistant Clinical Professor of Psychiatry at Harvard Medical School and Psychiatrist at the Massachusetts Institute of Technology, was a co-founder of the International Physicians for the Prevention of Nuclear War, recipient of the 1985 Nobel Peace Prize. Michael McCally is Lecturer in Medicine at the Pritzker School of Medicine at the University of Chicago. Howard Hu is Assistant Professor of Environmental Health at the Harvard School of Public Health. Andrew Haines is Professor and Head of the Department of Primary Health Care at University College London Medical School.