IBSI
| Acronym | Definition |
|---|---|
| IBSI | International Business Systems, Inc. |
| IBSI | International Bureau of Special Investigations (est. 2008; Florida) |
| IBSI | Integrated Business Services, Inc. (various locations) |
| IBSI | Immune Building Systems Inc. (New York, NY) |
| IBSI | Idaho Business Systems, Inc. (Pocatello, ID) |
| IBSI | Integrated Broadband Services, Inc. |