From SO2 to Greenhouse Gases: Trends and Events Shaping Future Emissions Trading Programs in the United States

The success of the United States sulfur dioxide (SO2) trading program has led to worldwide interest in emissions trading. The program has become a model for policymakers in the United States and in other countries that are considering cap-and-trade programs to reduce emissions. Once a theoretical option discussed only by economists, emissions trading is now considered a mainstream policy instrument in the United States with bipartisan political support. Internationally, emissions trading is no longer considered a crazy American idea. It is now a fundamental component of the international framework to address climate change. Even developing countries from Chile to China are beginning to consider emissions trading programs to control conventional pollutants (U.S. EPA 2004).