| IASC | Illinois Association of Snowmobile Clubs 
| Others |
| IASC | Illinois Association of Student Councils
| Others |
| IASC | Indian Army Service Corps
| Army |
| IASC | Indiana Association of Student Councils
| Others |
| IASC | Institute for Advanced Study Computer
| Others |
| IASC | Inter Agency Standing Committee
| Others |
| IASC | Inter-Agency Standing Committee
| Others |
| IASC | Interagency Standing Committee (UN)
| Others |
| IASC | Interim Acting Service Chief
| Others |
| IASC | International Accounting Standards Committee
| Others |
| IASC | International Aloe Science Council
| Others |
| IASC | International Arctic Science Committee
| Others |
| IASC | International Arctic Service Committee
| Others |
| IASC | International Association for Statistical Computing
| Others |
| IASC | International Association for the Study of Controversies
| Others |
| IASC | International Association for the Study of the Commons
| Others |
| IASC | International Association of Skateboard Companies
| Others |
| IASC | International Astronomical Search Collaboration
| Others |
| IASC | International Aviation Services Centre
| Others |
| IASC | Introducing Australia Studies Centre
| Others |
| IASC | Itasca Area Schools Collaborative
| Others |