| Abbreviation | Definition |
|---|---|
| ACQA | Ambulatory Care Quality Alliance |
| ACRAD | Alliance for Community Resilience And Development |
| ACRE | Alliance of Conservatives and Reformists in Europe |
| ACRES | Alliance for Clinical Research Excellence and Safety |
| ACRP | Alliance of Career Resource Professionals |
| ACRRA | African Caribbean Reparations and Resettlement Alliance |
| ACTA | Alliance for California Traditional Arts |
| ACTESA | Alliance for Commodity Trade in East and Southern Africa |
| ACTESA | Alliance for Commodity Trade in Eastern and Southern Africa |
| ACTO | Alliance of Concerned Transport Organizations |
| ACTRA | Arizona Cyber Threat Response Alliance |
| ACTS | Alliance for Community Transformation and Service |
| ADAA | Armenian Dramatic Arts Alliance |
| ADCA | Advanced Degree Consulting Alliance |
| ADDA | Alabama Drug Discovery Alliance |
| ADDE | Alliance for Direct Democracy in Europe |
| ADF | Alliance Defending Freedom |
| ADFAM | Alliance for the Defence of the Family And Marriage |
| ADG | Alliance de Gauche (French: Left Alliance; Switzerland) |
| ADML | Alliance Digital Medial Library |