| Acronym | Definition |
|---|
| SISS | Superintendencia de Servicios Sanitarios (Spanish: Superintendence of Sanitary Services; Chile) |
| SISS | Sistema Integral de Seguridad Social (Spanish: Integrated Social Security System; Colombia) |
| SISS | Sistema Informativo Socio Sanitario (Italian: Health Care Information System) |
| SISS | Smart Idling Stop System |
| SISS | Smart Idle Stop System (Mazda) |
| SISS | School of Islamic and Social Sciences (Leesburg, VA) |
| SISS | Services for International Students and Scholars (University of California) |
| SISS | Station Information and Security System (railway telecommunications; UK) |
| SISS | Southern Institute of Social Sciences (Vietnam) |
| SISS | Subcommittee on Information Systems Security of the NSTISSC |
| SISS | Standoff Imagery Sensor System |
| SISS | Sprint International Systems and Services Group |