DSO
- Dallas Symphony Orchestra
- Dark Sky Observatory
- Dark Star Orchestra
- Darwin Symphony Orchestra
- Days sales outstanding
- Deep-sky object
- Defence Science Organisation
- Defense Sciences Office
- Defensive Systems Officer
- Dental service organizations
- Denver Symphony Orchestra
- Detroit Symphony Orchestra
- Deutsches Symphonie-Orchester Berlin
- Diablo Swing Orchestra
- Digital storage oscilloscope
- Digital switchover
- Direct service organisation
- Direct shipping ore
- Directorate of Special Operations
- Distinguished Service Order (disambiguation)
- Diving safety officer
- Dobbertin Surface Orbiter
- Drakensang Online
- Dubai
- Dubai Silicon Oasis
- Dubrovnik Symphony Orchestra
- Dubuque Symphony Orchestra
- Dunedin Symphony Orchestra
- Dynamic shared object
- Electric power distribution
- Groupe DSO
- Sondok Airport