Population growth hastens the depletion of natural resources, degrades the environment, increases poverty and conflict, and debases the human spirit. This book offers an antidote. It prescribes a simple and practical credit-based system that can gradually reduce any population to an optimal size without imposing a limit on the number of children a couple can produce. It does this without requiring anyone to violate the moral precepts of any of the world's major faiths regarding birth control and abortion. And it shows how to use the same system to rationally regulate immigration. After presenting the plan, the author explores the demographic, social, environmental, and economic changes that would likely accompany population reduction, and proposes innovative solutions for some of our most pressing problems, including poverty. Anyone with an interest in the future of mankind and the conservation of the natural world will find this book informative, original, thought-provoking, and hopeful.