| Y 3.Ac 7 | National Commission on Aids (1987-1988) |
| Y 3.Ad 6 | Administrative Conference of the United States (1964-1995; 2010- ) |
| Y 3.Ad 9/1 | Advisory Committee on Fiscal Relations Study (1936-1937) |
| Y 3.Ad 9/2 | Advisory Committee on Education (1937-1939) |
| Y 3.Ad 9/3 | Advisory Council on Social Security (1938) |
| Y 3.Ad 9/4 | Advisory Committee on Voluntary Foreign Aid (1946-1953) |
| Y 3.Ad 9/5 | Advisory Commission on Universal Training (1946-1948) |
| Y 3.Ad 9/6 | Advisory Committee on Weather Control (1953-1957) |
| Y 3.Ad 9/7 | Advisory Commission on Information (1948-1968) |
| Y 3.Ad 9/8 | Advisory Commission on Intergovernmental Relations (1959-1996) |
| Y 3.Ad 9/9 | Advisory Commission on International Educational and Cultural Affairs (1961-1978) |
| Y 3.Ad 9/10 | Advisory Commission on the Arts (1961-1973) |
| Y 3.Ad 9/11 | Advisory Committee on Federal Pay (1971-1991) |
| Y 3.Ad 9/12 | United States Advisory Commission on Public Diplomacy (1978-2011) |
| Y 3.Ae 8 | Aeronautics Board (1916-1948) |
| Y 3.Af 8 | African Development Foundation (1984- ) |
| Y 3.Ag 8/1 | Commission to Investigate and Study Agricultural Credits in Europe (1913-1916) |
| Y 3.Ag 8/2 | Joint Commission of Agricultural Inquiry (1921-1922) |
| Y 3.Ai 7 | Aircraft Board (1917-1919) |
| Y 3.Ai 7/2 | Joint Commission on Airports (1929-1930) |
| Y 3.Ai 7/3 | Air Coordinating Committee (1946-1960) |
| Y 3.Ai 7/4 | Airways Modernization Board (1957-1958) |
| Y 3.Ai 7/5 | National Commission on Air Quality (1977-1980) |
| Y 3.Al 1 | Second Court of Commissioners of Alabama Claims (1882-1885) |
| Y 3.Al 1/2 | National Alcohol Fuels Commission (1978-1981) |
| Y 3.Al 1s | Alaska International Rail and Highway Commission (1956-1961) |
| Y 3.Al 1s/2 | Temporary Alaska Claims Commission (1964-1969) |
| Y 3.Al 1s/3 | Federal Reconstruction and Development Planning Commission for Alaska (1964) |
| Y 3.Al 1s/4 | Federal Field Committee for Development Planning in Alaska (1964-1965) |
| Y 3.Al 4 | Office of Alien Property Custodian (1917-1934) |
| Y 3.Al 16 | Commission on Disposition of Alcatraz Island (1963-1965) |
| Y 3.Am 3 | American Battle Monuments Commission (1923- ) |
| Y 3.Am 3/2 | American Samoan Commission (1926-1931) |
| Y 3.Am 3/3 | American Relief Administration (1919-1923) (conflicting stems in Andriot) |
| Y 3.Am 3/4 | American Commission for Protection and Salvage of Artistic and Historic Monuments in War Areas 91943-1946) |
| Y 3.Am 3/5 | American National Red Cross (1949-1952) |
| Y 3.Am 3/6 | American Revolution Bicentennial Administration (1973- 1977) |
| Y 3.An 4 | Federal Development Planning Committee for Appalachia (1964-1965) |
| Y 3.An 8 | Anthracite Coal Strike Commission (1902-1903) |
| Y 3.An 8/2 | Anthracite Coal Commission (1920) |
| Y 3.Ap 4/2 | Appalachian Regional Commission (1965- ) |
| Y 3.Ap 4/3 | Commission on Revision of the Federal Court Appellate System (1972-1973) |
| Y 3.Ar 1 | Commission on Erection of Memorials and Entombment of Bodies in Arlington Memorial Amphitheater (1921-1925) |
| Y 3.Ar 2 | Architect of the Capitol (1793- ) |
| Y 3.Ar 2/2 | U.S. Arctic Research Commission (1984- ) |
| Y 3.Ar 5 | Arlington Memorial Amphitheater Commission (1921-1960) |
| Y 3.Ar 5/2 | Arlington Memorial Bridge Commission (1913-1933) |
| Y 3.Ar 5/3 | Air Force-Navy Civil Committee on Aircraft Design Criteria (1948) |
| Y 3.Ar 7 | National Commission on Arthritis and Related Musculoskeletal Diseases (1975-1976) |
| Y 3.At 6 | Atlantic-Pacific Interoceanic Canal Study Commission (1964-1970) |
| Y 3.At 7 | Atomic Energy Commission (1946-1974) |
| Y 3.Av 5 | Aviation Advisory Commission (1970-1972) |
| Y 3.Av 5/2 | Aviation Safety Commission (1987-1988) |
