| Abbreviation | Definition |
|---|---|
| IEPHRO | International Environment Protection Human Rights Organization |
| IEPR | Illinois Environmental Policy Review |
| IEPT | Integrated Environmental Planning and Technology |
| IEQ | Indoor Environmental Quality |
| IEQC | Indoor Environmental Quality Credits |
| IER | Interdisciplinary Environmental Review |
| IERB | Indoor Environmental Remediation Board |
| IERE | Institute for Environmental Research and Education |
| IERG | Illinois Environmental Regulatory Group |
| IERI | International Electronics Recyclers Institute |
| IERS | Integrated Environmental Restoration Services |
| IES | Indoor Environmental Services |
| IES | Institute for Environmental Security |
| IES | Integrated Environmental Solutions |
| IES | Integrated Environmental Systems |
| IESA | Institute for Environmental Spatial Analysis |
| IESD | International Environmental Sustainable Development |
| IESE | Institute of Environmental Science and Engineering |
| IESE | Institute of Environmental Sciences Engineering |
| IESS | Indigenous Environmental Studies and Sciences |