CSG
- CSG International
- CSG Limited
- California State Guard
- Camden School for Girls
- Canadian Senators Group
- Carrier strike group
- Centre Spatial Guyanais
- Centrum Schwule Geschichte
- Chilean Sign Language
- China Shipping Group
- Citizens for Self-Governance
- Cloud Software Group
- Coal seam gas
- Columbus Airport (Georgia)
- Columbus School for Girls
- Common Sense Group
- Commonwealth Secretary-General
- Conseil supérieur de la guerre
- Constructible strategy game
- Constructive solid geometry
- Context-sensitive grammar
- Corps Support Group
- Czechoslovak Group
- Haeco-CSG
- MOS Technology
- Polycrystalline silicon photovoltaics
- The Council of State Governments