PPSI
| Acronym | Definition |
|---|---|
| PPSI | Project Preventie Seksuele Intimidatie (Dutch: Sexual Harassment Prevention Project; Utrecht, Netherlands) |
| PPSI | Pounds Per Square Inch |
| PPSI | Petroleum Philatelic Society International |
| PPSI | Paint Product Stewardship Initiative (est. 2005; Product Stewardship Institute) |
| PPSI | Pharmacists Planning Service, Inc. (health care; California) |
| PPSI | Printing Press Services International (UK) |
| PPSI | Porous Polyethylene Sheet Implant |