This concluding chapter reviews the key themes of the book and explores some of the broader implications of this analysis of California's regulatory leadership. Three points are particularly critical: the importance of the local dimension of environmental policies, the role of business in environmental politics, and the limits of environmental regulation. The chapter then discusses the increasingly important role states are playing in environmental protection in the United States and shows how California has economically benefited from its environmental policy leadership. One important reason why California has been able to consistently adopt more stringent regulations than those of the federal government and other states is that many of its improvements in local and state environmental quality have been a source of competitive advantage. The improvements it has made in air quality—most notably in Los Angeles—its protection of the trees in the Sierras and along the Pacific, and its land use controls along the coast and around the San Francisco Bay have all made California a more attractive place to move to, invest in, and visit.