Solar power satellites are the emerging energy option for meeting humanity's expanding energy requirements in an environmentally benign way. This book provides a comprehensive review of the current state of the art in this important and rapidly developing area, and contains chapters from experienced and renowned contributors. Topical and timely, the book provides a framework for taking the evolutionary steps needed to lessen dependence on non-renewable resources and presents an approach to mitigate global warming and ecological degradation. It addresses the technical, economic, institutional, and societal issues involved, and will become a prime text for all those involved in advancing our knowledge of the science and technology that with ultimately make accessible the vast energy resources available beyond the surface of the Earth.