ACG
- ACG (subculture)
- Academic Colleges Group
- Academic Competitiveness Grant
- Acocks Green railway station
- Acoustocerebrography
- Air Cargo Germany
- Air Combat Group RAAF
- American College for Girls
- American College of Gastroenterology
- American College of Greece
- American Comics Group
- Angiocardiography
- Associated Carrier Group
- Association for Corporate Growth
- Atlético Clube Goianiense
- Azeri-Chirag-Guneshli
- Roblox
- Ultimate Play the Game
- Área de Conservación Guanacaste