| Acronym | Definition |
|---|
| FMSI | Force Management System Interface |
| FMSI | Federazione Medico Sportiva Italiana (Italian: Italian Sports Medicine Federation; Italy) |
| FMSI | Folk Music Society of Ireland |
| FMSI | Financial Management Solutions, Inc. (est. 1990; Georgia) |
| FMSI | Friction Materials Standards Institute (est. 1948; Madison, CT) |
| FMSI | Sons of Mary, Health of the Sick (religious order) |
| FMSI | Frontier Management (Shanghai) Inc. (Shanghai, China) |
| FMSI | Fondazione Marista per la Solidarietà International (Italian: Marist Foundation for International Solidarity) |