| Abbreviation | Definition |
|---|---|
| CWSA | Coplay Whitehall Sewer Authority |
| CWTA | Cadillac Wexford Transit Authority |
| DA | Domain Authority |
| DAA | Designated Accrediting Authority |
| DACC | Development Authority of Cobb County |
| DAESA | DeWitt Area Emergency Services Authority |
| DALCA | Dominica Association of Local Authorities |
| DARTA | Detroit Area Regional Transportation Authority |
| DATA | Durham Area Transit Authority |
| DATO | Disapproval of Authority to Operate |
| DCFA | Delaware County Finance Authority |
| DCTA | Denton County Transit Authority |
| DCWASA | District of Columbia Water And Sewer Authority |
| DDA | Direct Debit Authority |
| DDRA | Dothan Downtown Redevelopment Authority |
| DDRTF | Drug Demand Reduction Task Force (Department of Defense; est. 1992) |
| DESA | Defence Explosives Safety Authority |
| DEWA | Dubai Electricity Water Authority |
| DHAI | Defence Housing Authority, Islamabad |
| DHNA | Dart Harbour and Navigation Authority |