| Abbreviation | Definition |
|---|---|
| IHS | International Hair Society |
| IHS | International Headache Society |
| IHS | International Hearing Society |
| IHS | International Horn Society |
| IHT | Institution of Highways & Transportation |
| IIA | Indian Institute of Architects |
| IIA | Istituto Italiano degli Attuari |
| IIA | Italian Institute of Actuaries |
| IIAS | Institut International des Sciences Administratives |
| IIC | Institute of Chilean Engineers |
| IIC | Instituto de Ingenieros de Chile |
| IIChE | ÐÒÕÓÔ ÙéèÐÜÙê ÜÔàÓáÔ ÛÙÞÙê |
| IIE | Institute of Engineering of Spain |
| IIE | Instituto de la Ingeniera de Espaa |
| IIE | Instituto de la Ingeniería de España |
| IIEA | Institute of Industrial Engineers Australia |
| IIEE | Institute of Integrated Electrical Engineers |
| IIF | Institut International du Froid |
| IIF | International Institute of Refrigeration |
| IIFS | India International Friendship Society |