- American Society of Newspaper Editors1
- American Society of University Composers3
- American Standard Jewelry Co.1
- American Supply Co.1
- American Surety Company6
- American System-Built (Firm)1,103
- American Tract Society1
- American Tube & Stamping Co.1
- American Wholesale Corporation1
- Americans for Democratic Action2
- Ames Cunehan and Newman, Inc.1
- Ames, David1
- Ames, Fisher, 1758-18083
- Ames, Genie1
- Ames, Jessie Daniel, 1883-19722
- Ames, William T1
- Amherst College. Library1,634
- Amherst of Arracan, William Pitt Amherst, Earl, 1773-185738
- Amherst, Elizabeth, 1739 or 1740-183017
- Amherst, Jeffery Amherst, Baron, 1717-17971
- Amilcar, Amanda1
- Amin, Samir1
- Amiri Baraka's Blue Ark (Musical group)2
- Amirian, Adrianne2
- Amitay, Morris J., 1936-1
- Amnesty International USA1
- Amor Building Corp.1
- Amos House (Shelters : Providence, R.I.)1
- Amos, Stanley2
- Amparo1
- Ampir Realty Corp.1
- Amram, David28
- Amundsen, Kathleen, 1960-1
- An, Ik-t'ae, 1906-19652
- Anagarika Govinda, Lama, 1898-19852
- Anasa, Kimako1
- Ancier, Garth, 1957-1
- Andersen, Anders Højmark21
- Andersen, Eric4
- Anderson & Krum Stationery Co.2
- Anderson & Price1
- Anderson Avenue Park Plaza Corp.1
- Anderson Carriage Co.1
- Anderson Water, Light & Power Company1
- Anderson and Bremer1
- Anderson, Abraham, 1954-3
- Anderson, Adolph2
- Anderson, Alexander, 1775-18701
- Anderson, Beth, 1950-1
- Anderson, Carolyn, 1913-19931
- Anderson, Clinton Presba, 1895-19751
- Anderson, Dillon, 1906-19741
- Anderson, Donald (Cellist)1
- Anderson, Florence, 1910-143
- Anderson, G. Early1
- Anderson, Gilbert M., 1880-19711
- Anderson, Harold S1
- Anderson, Helen1
- Anderson, Jack Z. (Jack Zuinglius), 1904-19811
- Anderson, James1