James Lovelock's Gaia theory, which views the earth as a living organism, is widely seen as a vital change in our scientific and cultural outlook on the planet we inhabit. As the developed--and developing--worlds grapple with problems of sustainability on a planetary scale, the implications of Gaia theory are both urgent and critically important. The contributors include James Lovelock, Lynn Margulis, Brian Goodwin, Mae Wan Ho, Peter Saunders, Kate Rawles, and others. They seek to define what is meant by Gaia, and to translate the theory into practical ways of relating to the planet as a whole.