The Architect of the Capitol is charged with the operation and maintenance of the buildings committed to his care by Congress. Permanent authority for the care and maintenance of the United States Capitol was established by the Act of August 15, 1876 (19 Stat. 147; 40 U.S.C. 162–163). The Architect’s duties include the mechanical and structural maintenance of the building, the upkeep and improvement of the Capitol grounds, and the arrangement of inaugural ceremonies and other ceremonies held in the building or on the grounds. Legislation has been enacted over the years to place additional buildings and grounds under the jurisdiction of the Architect of the Capitol.

Today, in addition to the Capitol, the Architect is responsible for the upkeep of all of the congressional office buildings, the Library of Congress buildings, the United States Supreme Court building, the Thurgood Marshall Federal Judiciary Building, the Capitol Power Plant, the Capitol Police headquarters, and the Robert A. Taft Memorial. The Architect performs his duties in connection with the Senate side of the Capitol, the Senate Office Buildings, and the operation of the Senate Restaurants subject to the approval of the Senate Committee on Rules and Administration. In matters of general policy in connection with the House Office Buildings and the Capitol Power Plant, his activities are subject to the approval and direction of the House Office Building Commission. The Architect is under the direction of the Speaker in matters concerning the House side of the Capitol; with respect to many administrative matters affecting operations on the House side of the Capitol complex he is subject to the oversight of the Committee on House Administration. He is responsible for the care and repair of works of art in the Capitol under the direction of the Joint Committee on the Library; in addition, he is responsible for the maintenance and restoration of murals and other architectural elements throughout the Capitol complex. The Architect of the Capitol also serves as the Acting Director of the United States Botanic Garden under the Joint Committee on the Library.

Until 1989 the position of Architect of the Capitol was filled by Presidential appointment for an indefinite term. Legislation enacted in that year (Public Law 101–163) provides that the Architect is to be appointed for a 10-year term by the President, with the advice and consent of the Senate, from a list of three candidates recommended by a congressional commission. Upon confirmation by the Senate, the Architect becomes an official of the Legislative Branch as an officer and agent of Congress; he is eligible for reappointment after completion of his term. Mr. Alan Hantman, FAIA, the 10th Architect of the Capitol (confirmed in 1997), was the first Architect to be appointed under the procedure established by this legislation.

Dr. William Thornton, whose design for the Capitol was selected by President George Washington after a national architectural competition in 1793, is honored as the first Architect of the Capitol. Dr. Thornton’s assignment was limited to designing and supervising the construction of the new Capitol, under the direction of the Commissioners of the Federal District and the President of the United States. However, the role and responsibilities of the Architect have changed and grown as additional activities have been assigned to the office by Congress. Today, in light of the widespread activities under the jurisdiction of the Architect of the Capitol, the administrative function of the office is as important as the architectural and engineering responsibilities.

Projects carried out by the Architect of the Capitol include restoration of the frescoed Capitol Rotunda canopy and frieze and the Statue of Freedom; restoration of the west central front of the Capitol and the Olmsted terraces; completion of the murals in the first-floor House corridors; and installation of an improved Senate subway system. The agency also oversaw the design and construction of the Thurgood Marshall Federal Judiciary Building and effected the renovation, restoration, and modification of the Library of Congress Thomas Jefferson and John Adams Buildings.

Current projects under the direction of the Architect of the Capitol include replacement of worn Minton tile in the Senate corridors of the Capitol; renovation of hearing rooms and other spaces and the improvement of electrical, fire-protection, plumbing, and transportation systems in the Capitol and Congressional office buildings; installation of perimeter security devices across the Capitol complex; renovation of the U.S. Botanic Garden Conservatory; development of a Capitol Complex Master Plan; expansion and modernization of the Capitol Power Plant; modernization of the Supreme Court building and the construction of an underground annex; and construction of the Capitol Visitor Center.

The Architect of the Capitol serves as a member of the following governing or advisory bodies: Capitol Police Board, Capitol Guide Board, District of Columbia Zoning Commission, Advisory Council on Historic Preservation, National Capital Memorial Commission, Art Advisory Committee to the Washington Metropolitan Area Transit Authority, and the National Institute for Conservation of Cultural Property. He is also an ex-officio member of the United States Capitol Preservation Commission.