| International Agency for Research on Cancer | International Agency for research on Cancer |
| International Air Transport Association | International Air Transport Association |
| International Baccalaureate Diploma Programme | International Baccalaureate |
| International Bank Account Number | International Bank Account Number |
| International Civil Aviation Organization | International Civil Aviation Organization |
| International Code of Botanical Nomenclature | Botanische nomenclatuur |
| International Code of Nomenclature for Cultivated Plants | ICNCP |
| International Commission on Stratigraphy | International Commission on Stratigraphy |
| International Cricket Council | ICC |
| International Electrotechnical Commission | International Electrotechnical Commission |
| International Maritime Organization | International Maritime Organization |
| International Music Score Library Project | International Music Score Library Project |
| International Plant Names Index | International Plant Names Index |
| International Security Assistance Force | International Security Assistance Force |
| International Standard Book Number | Internationaal Standaard Boeknummer |
| International Standard Serial Number | ISSN |
| International style | Internationale Stijl |
| International Tchaikovsky Competition | Internationale Tsjaikovskiwedstrijd |
| International Tennis Federation | International Tennis Federation |
| International Tennis Hall of Fame | Tennis Hall of Fame |
| International Union of Socialist Youth | International Union of Socialist Youth |
