Lombard analyzes the complementary relationship between trade and the environment in the emerging North American environmental management system comprising Canada, the United States, and Mexico. He views the development of closer trade relations among the three NAFTA members as having an overall and long-term beneficial impact on the environment, particularly air quality, in North America. He presents a revised model of environmental policy implementation which stresses further decentralization of environmental protection enforcement, greater reliance on nongovernmental organizations, including businesses, in environmental policy decisionmaking, and the fostering of regional approaches to resolving environmental problems.