The book interprets nature and the environment as a scarce resource. It offers a theoretical study of the allocation problem and describes different policy approaches to the environmental problem. The entire spectrum of the allocation issue is studied. The author incorporates several economic approaches, including neoclassical analysis, the public goods approach and optimization theory. The different aspects of environmental allocation are studied in the context of a single model that is used throughout the book. The sixth edition includes new sections on ethical aspects of environmental evaluation, and international emission trading and biodiversity.