| Abbreviation | Definition |
|---|---|
| PJI | Pacific Justice Institute |
| PJN | Peace & Justice Network of San Joaquin County |
| PK | Promise Keepers |
| PKDF | Polycystic Kidney Disease Foundation |
| PKF | Pollock-Krasner Foundation |
| PKF | Polly Klaas Foundation |
| PKO | Protect Kahoolawe Ohana |
| PLAR | Promised Land Animal Rescue |
| PLDC | Production Limiting Disease Committee |
| PLF | Pacific Legal Foundation |
| PLF | Penguin Liberation Front |
| PLF | People's Legal Front |
| PLF | Pittsburgh Leadership Foundation |
| PLF | Points of Light Foundation |
| PLF | Public Land Foundation |
| PLF | Public Lands Foundation |
| PLIC | Protect Lummi Island Community |
| PLMP | Philippine Library Materials Project Foundation, Inc. |
| PLMX | Product Lifecycle Management eXchange |
| PLTW | Project Lead The Way |