摘要：Since its creation in 1970, the Environmental Protection Agency (EPA) has promulgated an array of "command and control" regulations that specify the methods and technologies firms must use to control pollution. Recognizing that this regulatory approach is often unduly expensive, EPA began in 1974 to experiment with alternatives that allow firms greater flexibility in meeting, national air quality goals. Since then, the Agency has developed and implemented an ambitious policy-emissions trading-that allows firms to trade rights to emit air pollutants. According to EPA administrator Lee Thomas, emissions trading has become "one of EPA's most impressive accomplishments."
