The Petitioners sought orders to set aside a license to construct a pumped storage hydroelectric project on the Hudson River. Under the Federal Power Act, in order to be licensed by the Federal Power Commission a prospective project had to meet the statutory test of being “best adapted to a comprehensive plan for improving or developing a waterway.” The Commission therefore had to compare the project with available alternatives and only grant the application if no better adapted alternatives were available. The Court held that for the Commission to discharge its duty properly the record on which it based its decision had to be complete. In this case the Commission had failed to compile a record which was sufficient to support its decision. It had ignored relevant factors and failed to conduct a thorough study of the possible alternatives to the project. The Commission’s order was therefore set aside.