Editors' Summary: The gray-bearded Clean-Air Act may appear to be enjoying a quiet slumber in the lull between its 1982 and 1987 deadlines for eliminating unhealthy air pollution, but it is not. The pages of the Federal Register and the federal court reporting services are crammed with legal developments under the Act. They receive relatively little attention in comparison to Congress' futile efforts to give the Act its second major overhaul since 1970, not to mention the general hullabaloo over hazardous waste, but they are important. Lacking guidance from Congress, EPA has reshaped the Act and its implementation, refining the basic regulatory tools, charting administrative paths around the potentially disastrous 1982 attainment deadline, and giving the states increasing implementation authority. EPA also has had its hands full trying, with mixed success, to fend off states' and environmentalists' efforts to force the agency to expand regulation of toxic air pollutants and emissions of sulfur dioxide, the pollutant most often cited as a cause of acid rain. The author reviews 1984 judicial and administrative actions under the stationary source provisions of the Clean Air Act and concludes that EPA has rebuilt the Act into a slimmed-down, stripped-down model that can continue forward without major breakdown largely because it skirts the major challenges posed by the Act's 1977 Amendments.