| Abbreviation | Definition |
|---|---|
| ICPA | International Cast Polymer Alliance |
| ICR | Institute of Cancer Research |
| icr | Institute of Clinical Research |
| ICRA | Internet Content Rating Association |
| ICRAN | International Coral Reef Action Network |
| ICRC | International Committee of the Red Cross |
| ICRSE | International Committee on Rights of Sex Workers in Europe |
| ICRW | International Center for Research on Women |
| ICS | International Continence Society |
| ICSA | International Communal Studies Association |
| ICSB | International Council for Small Business |
| ICSF | Inner-City Scholarship Fund |
| ICSF | International Children's Surgical Foundation |
| ICSF | Internet Child Safety Foundation |
| ICSF | Ironton City Schools Foundation |
| ICSF | Ivy Community Service Foundation of Cary |
| ICSI | Institute for Clinical Systems Improvement |
| ICSI | International Consumer Support for Infertility |
| ICSO | Indigenous Cambodian Support Organization |
| ICSP | Institut canadien pour la sécurité des patients |