| Analog Television Systems Corporation | Business |
| Administrative Technology Service Center | Business |
| Advanced Television Systems Committee | Community |
| Advanced Television Standards Committee | Community |
| American Television Systems Committee | Community |
| Advanced Tv Systems Committee | Community |
| Arlington Travel Soccer Club | Community |
| Advanced Televisions Systems Committee | Community |
| Air Travellers Security Charge | Community |
| Advanced Technology Studies Centre | Computing |
| Academic Technology Support Center | Computing |
| Accurate Tilt Servo Control | Computing |
| Advanced Technology Systems Company | Computing |
| Annihilate Terrestrial Service Completely | General |
| Assessment And Treatment Services Center | General |
| Any Time Some Color | General |
| Affiliated Tyreright Service Centre | General |
| Alpha Team Space Command | General |
| Atlantique Technique Soudage Coupage | General |
| Air Traffic Security Coordinator | General |
| Active Traction and Stability Control | General |
| American Traffic Signal Company | General |
| Adaptive Traffic Signal Control | General |
| All Terrain Stand on Cycle | General |
| Arkansas Tobacco Settlement Commission | General |
| Army Training Support Center | Governmental |
| AlliedSignal Technical Services Corporation | Governmental |
| Aviation Electronics Technician (asw) Chief Petty Officer | Governmental |
| Autism Treatment Services Of Canada | Regional |
| Apparel Textile Sourcing Canada | Regional |
| Athletic Training Service Center | Sports |
| Advanced Total Soccer Coaching | Sports |