- AECOM (Firm)1
- Adamchak, Raoul W., 1953-1
- Adams, Glenn B.1
- Albanese, Naomi G., 1916-19891
- Alpi, Kristine M.1
- American Society for the Prevention of Cruelty to Animals5
- Anderson, Allison1
- Anderson, Donald B., 1899-19941
- Anderson, Jordan Shai1
- Animal Rights Network15
- Animal Welfare Institute4
- Arey, John A., 1887-19851
- Arnold, Bill (William Malloy)1
- Atkins, John L., III1
- Augustyn, Veronica1
- Ausley, Wally3
- Baker, Alen D.1
- Barker, K. R. (Kenneth Reece), 1932-1
- Barnhardt, Robert A.1
- Basile, Don (Donald E.)1