| Psychology Instructional Resource Center | Academic & Science |
| Pensions Investment Research Consultants | Academic & Science |
| Project Implementation Review Committee | Business |
| Property Insurance and Restoration Conference | Business |
| Pensions & Investments Research Consultants | Business |
| Park Incremental Revenue Capture | Community |
| Permanent Identity Relationship Culture | Community |
| Per Interface Rate Control | Computing |
| Primary Infection Resource Consortium | General |
| Polyposis In Rat Coli | General |
| Parent Information and Resource Center | General |
| Parental Information and Resource Centers | General |
| Proportional Item Response Curve | General |
| Pittsburgh International Race Complex | General |
| Procurement Innovation Resource Center | General |
| Purge Interval Replication Control | General |
| Property Information Resource Center | General |
| Plastics Innovation Resource Center | General |
| Percussion Induced Rapid Contraction | General |
| Platelet Indirect Radioactive Coombs | General |
| Polyposis In the Rat Colon | General |
| Polyposis In Rat Colon | General |
| Public Interest Resource Center | General |
| Police Investigations and Review Commissioner | Governmental |
| Portland Immigrant Rights Coalition | Governmental |
| Program to Improve Reserve Components | Governmental |
| Pennsylvania Immigration Resource Center | Governmental |
| Psychiatric Intake Response Center | Medical |
| Prevention Innovations Research Center | Medical |
