| Acronym | Definition |
|---|
| IISF➣Istituto Italiano per gli Studi Filosofici (Napoli, Italy) |
| IISF➣International Information Science Foundation (computer science research program; Minato-ky, Tokyo, Japan; est. 1987) |
| IISF➣International Institute of San Francisco |
| IISF➣International Information Security Foundation (internet security) |
| IISF➣International Institute for Sustainable Future |
| IISF➣Israel Ice Skating Federation |