For years, attempts by states and localities to regulate vehicular emissions have been thwarted by the Supreme Court’s environmental preemption doctrine. These preemption cases emphasize textual, plain-meaning interpretations of the Clean Air Act and the Energy Policy and Conservation Act, which facially preempt any state emission standard inconsistent with federal law. Recent developments in preemption doctrine, however, have emphasized both the presumption against preemption and the importance of cooperative federalism, concepts absent from the Court’s contemporary environmental preemption cases. A more proper balance between federal and state regulation can be found. Namely, the Court should align environmental preemption cases with the more recent preemption developments and give greater weight to legislative purpose. Doing so will give states and localities some power to regulate emissions, while protecting federal interests in the uniformity and commercial feasibility of standards.