Interlibrary loan

Interlibrary loan (abbreviated ILL, and sometimes called interloan, interlending, document delivery, or document supply) is a service whereby a user of one library can borrow books or receive photocopies of documents that are owned by another library. The user makes a request with their local library, which, acting as an intermediary, identifies owners of the desired item, places the request, receives the item, makes it available to the user, and arranges for its return. The lending library usually sets the due date and overdue fees of the material borrowed. Although books and journal articles are the most frequently requested items, some libraries will lend audio recordings, video recordings, maps, sheet music, and microforms of all kinds. In many cases, nominal fees accompany interlibrary loan services.

The term document delivery may also be used for a related service, namely the supply of journal articles and other copies on a personalized basis, whether these come from other libraries or direct from publishers. The end user is usually responsible for any fees, such as costs for postage or photocopying. Commercial document delivery services will borrow on behalf of any customer willing to pay their rates.

Interlibrary loan, or resource sharing, has two operations: borrowing and lending.

Interlibrary loan and resource sharing have a variety of systems and workflows, often based on the scale of service, regional networks, and library systems. Processes are automated by computer systems such as VDX based on ISO ILL standards 10161 and 10160. Additional Interlibrary Loan systems are used widely with two major systems used heavily: ILLiad developed by Atlas Systems and Worldshare Management System by OCLC

Loan requests between branch libraries in the same local library system are usually filled promptly, while loan requests between library systems may take weeks to complete. However, if an item is rare, fragile, or exceptionally valuable, the owning library is under no obligation to release it for interlibrary loan. Some collections and volumes, especially bound journals and one-of-a-kind manuscripts, are non-circulating, meaning that they may not be borrowed. Books may be delivered by mail or courier service. Photocopies may be faxed or scanned and delivered electronically. Urgent requests are placed if the item is needed right away, sometimes for additional fees. Public libraries do not usually offer urgent service.

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Wikipedia