| Abbreviation | Definition |
|---|---|
| ATAA | Arts Touring Alliance of Alberta |
| ATCA | African Tobacco Control Alliance |
| ATEST | Alliance to End Slavery and Trafficking |
| ATEST | Alliance to End Slavery Trafficking |
| ATID | Alliance for Teens in Detroit |
| ATIS | Alliance for Telecommunications Industry Solutions |
| ATLC | Alliance for Transforming the Lives of Children |
| ATOP | Alliance Treaty Obligations And Provisions |
| ATRA | Alberta Tobacco Reduction Alliance |
| ATTA | Albemarle Truth in Taxation Alliance |
| AUA | Assyrian Universal Alliance |
| AUKUS | Australia, United Kingdom, United States |
| AVA | Alliance for the Visual Arts |
| AVA | Alliance of Valliant Arms |
| AVIT | Alliance of and for Visually Impaired Texans |
| AWA | American Wrestling Alliance |
| AWAKE | Alliance of Women Achieving Knowledge and Excellence |
| AWARE | Alliance of White Anti Racists Everywhere |
| AWD | Alliance of Women Directors |
| AWE | Alliance for Water Efficiency |