Since the 'environmental revolution' began in the late 1960s, ecomists have done a lot of work in the field of ecomic theory-building on the preservation of nature. Meanwhile, environmental ecomic literature has swelled to a large stream of articles in journals of different signature. As a result, a coherent ecomic view of the phemen ofenvironmental degradation has emerged. Several kinds of 'green' public policies and their impacts on both nature and the performance of the ecomy have been analysed. The feasibility ofspecific types of policy has also been discussed. The aim of the book is to provide an insight into the ways ecomists analyse the problems ofenvironmental pollution and the depletion ofnatural resource. To this purpose a number of articles have been selected. Some of them have a fundamental character, others an applied nature and are foremost, practically oriented. The presentation of the collection emphasizes our belief that ecomists are able to deliver an essential contribution to the design of policies to protect nature. It is clear that 'nature' and 'environment' may longer be regarded as 'free gifts' to society. Rather, they have to be seen as scarce resources, and environmental disruption and resource depletion as allocation problems. Ifa natural resource is scarce, a price must be charged in accordance with the degree ofscarcity since otherwise society will be confronted with misallocations. In this connection there are two topics which are of particular interest to ecomists.