| Abbreviation | Definition |
|---|---|
| IESD | Institute of Environment for Sustainable Development |
| IESDA | Institute of Environment and Sustaianble Development in Agriculture |
| IESL | Institution of Engineers Sri Lanka |
| IESM | Institute Of Engineering Science Management |
| IESP | Institute for Earth System Preservation |
| IESP | Institute for Education and Social Policy |
| IESR | Institute For Economic And Social Research |
| IESR | Institute for Environment Sustainability and Regeneration |
| IESR | Institute for Essential Service Reform |
| IESS | Institute for Environment and Sanitation Studies |
| IESS | Institute Of Exercise Sports Science |
| IET | Institute of Engineerig Technology |
| IET | Institute of Engineering of Technology |
| IETE | Institute of Electronics and Telecommunication Engineers |
| IETI | International Engineering and Technology Institute |
| IETL | Institute for Education Teaching Leadership |
| IETL | Institute for European Traffic Law |
| IETL | Institute for Excellence in Teaching and Learning |
| IETR | Institute of Electronics and Telecommunications of Rennes |
| IEY | Institute for Early Years |