| Abbreviation | Definition |
|---|---|
| IUCH | International Union for Circumpolar Health |
| IUCN | International Union for the Conservation of Nature and Natural Resources |
| IUCN | World Conservation Union |
| IUCr | International Union of Crystallography |
| IUE | 564C=0@>4=K9 !>N7 -:>=><8AB>2 |
| IUE | International Union of Economists |
| IUE | Me~dunarodnyj Soûz Èkonomistov |
| IUE | Medunarodnyj Soz konomistov |
| IUES | Israel Underwater Exploration Society |
| IUFoST | International Union of Food Science and Technology |
| IUFRO | International Union of Forestry Research Organizations |
| IUGG | Union de Géodésie et Géophysique Internationale |
| IUGG | Union de Godsie et Gophysique Internationale |
| IUGS | Internationale Union fr Geologische Wissenschaften |
| IUGS | Internationale Union für Geologische Wissenschaften |
| IUGS | Unin Internacional de Ciencias Geolgicas |
| IUGS | Unión Internacional de Ciencias Geológicas |
| IUGS | Union Internationale des Sciences Géologiques |
| IUGS | Union Internationale des Sciences Gologiques |
| IUGW | International Union of Geological Sciences |