| Abbreviation | Definition |
|---|---|
| IEL | IET Electronic Library |
| IELS | Islington Education Library Service |
| IESA | Institutional Electronic Subscription Agreement |
| IESR | Information Environment Service Registry |
| IFLA | International Federation of Library Associations |
| IFLA | International Federation of Library Associations and Institutions |
| IFLA | International Function of Library Association |
| IFLASLB | International Federation of Library Associations and Institutions, Section of Libraries for the Blind |
| IFLL | International Friends of The London Library |
| IFLS | Indianhead Federated Library System |
| IFRT | Intellectual Freedom Round Table |
| IGMDP | Integrated Guided Missile Development Program |
| IHOC | International Healthcare Opportunities Clearinghouse |
| IHSL | Idaho Health Sciences Library |
| IIL | IAN Image Library |
| IJLM | International Journal of Library Management |
| IJLS | International Journal of Library Science |
| ILA | Idaho Library Association |
| ILA | Indian Library Association |
| ILA | Iowa Library Association |