This Essay addresses the Supreme Court’s recent decision in Federal Energy Regulatory Commission v. Electric Power Supply Association. The decision has received a level of popular attention that is almost unprecedented for a case involving electricity regulation. Nevertheless, one of the decision’s most jurisprudentially significant aspects has gone largely unnoticed. In ruling for FERC, the Court adopted a deeply functionalist approach to the Federal Power Act’s division of jurisdiction between state and federal regulators. In so doing, the Court cited with approval a number of pragmatic steps that FERC took to manage the jurisdictional challenges posed by new technologies for generating and consuming electricity. This is a laudable development. As the Essay explains, this functionalist approach will empower FERC to adapt the FPA to meet these new challenges while nevertheless remaining consistent with the FPA’s overarching purpose.