The Inflation Reduction Act (IRA) of 2022 added seven new sections to the Clean Air Act (CAA) and provided the U.S. Environmental Protection Agency (EPA) with substantial new authorities and resources. This Article examines these new amendments and the EPA-related provisions of the IRA, and explains the major implications of this historic legislation. It describes how the IRA confirms that reduction of greenhouse gases (GHGs) is a core goal of the CAA, that the funding provided should allow EPA to increase the ambition of its CAA rulemakings, and that the IRA confirms applicability of the CAA to GHGs in three important, specific areas: California’s ability to regulate GHG emissions from vehicles; EPA’s authority to regulate methane emissions from oil and gas facilities; and EPA’s authority to regulate GHG emissions from power plants.