The main contribution to this reader is a revised version of a study that has had a major impact on the political debate in Germany. In the study, which was commissioned by Greenpeace, the Deutsches Institut fur Wirtschaftsforschung (DIW), Berlin, examined the economic effects of an ecological tax reform, taking as an example a tax on energy. The study shows that such a tax reform is economically acceptable and environmentally positive even if implemented in one `pioneer' country alone.