| Abbreviation | Definition |
|---|---|
| IPPC | Integrated Pollution Prevention Control |
| IPPD | Intellectual Property Policy Directorate |
| IPRA | Internet Policy Registration Authority |
| IPRC | Identification, Placement, and Review Committee |
| IPS | Integrity, People, And Service |
| IPV6 | Internet Protocol version 6 |
| IPVV | Independent Price Verification and Valdation |
| IPvX | Internet Protocol version X |
| IQ | Information Qualification |
| IQ | Integrity Quotient |
| IQC | Incoming Quality Control |
| IR | Immunization Registry |
| IR | Industrial Reform |
| IRAA | Immigration Restructuring and Accountability Act of 1999 |
| IRAC | Issue Rule Analysis And Conclusion |
| IRAD | Independent Research And Development |
| IRAs | Individual retirement arrangements |
| IRB | Internal Review Board |
| IRC | Internal Revenue Code |
| IRFA | initial regulatory flexibility analysis |