The Single European Act will stimulate benefit assessment of environmental measures in all E.C. Member States and the aim of this book is to prepare guidelines for the assessment of such benefits. The book commences with a desciption of the methodologicalbackground of benefit assessment, and goes on to describe policy makers' views on benefit assessement in a number of countries including the U.S.A. An inventory and summary of key case studies is then provided: these will provide particularly valuable guidance for those involved in benefit assessments of environmental measures. An overview is then presented of the use of environmental benefit assessment for decision-making within the E.C. Commission. Guidelines are provided for carrying out a benefit assessment in practice, and finally conclusions and recommendations are presented.