National Airport was owned and operated by the Federal Government. The airport was first managed by the Civil Aeronautics Agency, a division of the Commerce Department. In 1959, control of National shifted to the newly created Federal Aviation Administration (FAA). Congress authorized construction of a second major airport to serve the Washington area, it again provided for federal ownership and operation. Dulles International Airport (Dulles) was opened in 1962 under the direct control of the FAA. National and Dulles are located in Virginia. National is located at the center of the metropolitan area with flight paths over densely populated areas. Local residents are concerned about safety, noise, and pollution. The Secretary of Transportation concluded that necessary capital improvements could not be financed for either National or Dulles unless control of the airports was transferred to a regional authority with power to raise money by selling tax-exempt bonds. All the local governments got together and agreed on the formation of D. Congress agreed to the proposal but required the formation of a review board with veto power over major actions of D's directors. This Board of Review was to consist of nine Members of Congress, eight of whom serve on committees with jurisdiction over transportation issues and none of whom may be a Member from Maryland, Virginia, or the District of Columbia. D was to submit to the Board of Review its a budget, authorization of bonds, promulgation of regulations, endorsement of a master plan, and appointment of the chief executive officer of D. The Board of Review had veto authority over D. All the legislation was approved and D adopted bylaws providing for the Board of Review. Citizens (P) brought this action. seeking a declaration that the Board of Review's power to veto actions of D is unconstitutional and an injunction against any action by the Board of Review as well as any action by D that is subject to Board of Review approval. The District Court granted Ds' motion for summary judgment. The District Court concluded that there was no violation of the doctrine of separation of powers because the members of the Board of Review acted in their individual capacities as representatives of airport users, and therefore the Board was not an agent of Congress. Also, the Board's powers were derived from the legislation enacted by Virginia and the District, as implemented by D's bylaws, rather than from the Transfer Act. Congress exercised no federal power under the Act, and thus it did not overstep its constitutionally-designated bounds. The court of appeals reversed holding that the Board was 'in essence a congressional agent' with disapproval powers over key operational decisions that were 'quintessentially executive,' and therefore violated the separation of powers. D appealed.