SGSI
| Acronym | Definition |
|---|---|
| SGSI | Shell Global Solutions International (oil exploration) |
| SGSI | Stabilized Glide Slope Indicator |
| SGSI | Schlosser Geographic Systems, Inc. (est. 1992; Seattle, WA) |
| SGSI | Stratos Government Services, Inc. (est. 2006; Washington, DC) |
| SGSI | Slovenian Genealogy Society International (est. 1986) |