| Abbreviation | Definition |
|---|---|
| IWSSD | International Workshop on Software Specification and Design |
| IWTC | International water technology conference |
| IWTC | Irish Web Technology Conference |
| IWW | International Writers Workshop |
| IWW | Internet World Wireless conference |
| IWWAN | International Workshop on Wireless Ad-hoc and Sensor Networks |
| IYC | International Youth Conference |
| IYCE | International Youth Conference on Energy |
| IYLC | Indonesia Youth Leadership Conference |
| IYLC | International Youth Leader Conference |
| IYLC | International Youth Leadership Conference |
| IYS | Idaho Youth Summit |
| IZC | International Zeolite Conference |
| JAAC | Jakarta Athletic Activities Conference |
| JAEC | Joint Arts Education Conference |
| JAEC | Junior Anglican Evangelical Conference |
| JAHC | Joint American Homeopathic Conference |
| JASPA | Jesuit Association of Student Personnel Administrators |
| JBCC | Jonathan M Borwein Commemorative Conference |
| JCAP | Jesuit Conference of Asia Pacific |