| Acronym | Definition |
|---|
| IPEN➣International POPs (Persistent Organic Pollutant) Elimination Network |
| IPEN➣Instituto Peruano de Energía Nuclear (Peruvian Nuclear Energy Institute) |
| IPEN➣Instituto Peruano de Energía Nuclear (Peru) |
| IPEN➣International Program Evaluation Network (conference) |
| IPEN➣Intellectual Property Enforcement Network |
| IPEN➣International Private Equity Network (various locations) |