The use of tradable permit systems for the protection of the environment is attracting growing interest in many countries and on the international scene. While the United States’ practice has been extensively analysed, relatively little is known of experiments in other countries. This book reviews the issues related to the implementation of domestic tradable permits systems in different areas (air, water, land) and in several OECD countries. It addresses key questions such as : what lessons can be drawn from existing experience? Why has the introduction of tradable permits failed in some instances? How can tradable permits be combined with other policy instruments such as taxes? What are the competitiveness implications of tradable permit systems? Not only should the lessons drawn from existing experience help the further use of domestic systems, it should also provide helpful insights for the possible implementation of tradable permits at the international level, in particular for managing greenhouse gases.