CSIU
| Acronym | Definition |
|---|---|
| CSIU | Central Susquehanna Intermediate Unit (Pennsylvania) |
| CSIU | Corrective Services Investigation Unit (Queensland, Australia) |
| CSIU | Core Segment Interface Unit (NASA) |
| CSIU | Crime Scene Investigation Unit |
| CSIU | Customer Satisfaction Information Usage |
| CSIU | Combat System Interface Unit |