| Acronym | Definition |
|---|
| ISPP | International Society of Political Psychology |
| ISPP | International Sewage Pollution Prevention Certificate (shipping; various locations) |
| ISPP | International Society for Plant Pathology |
| ISPP | International School of Phnom Penh (Cambodia) |
| ISPP | Information Support Pro Bono Platform |
| ISPP | Illinois School of Professional Psychology |
| ISPP | Illinois State Physics Project |
| ISPP | Integrated Sponsor's Program Proposal |
| ISPP | Individualized Sleep Promotion Plan |
| ISPP | Information Security Placement Professional |
| ISPP | Information System Program Plan |
| ISPP | Israel Society of Physiology & Pharmacology |