Direct answer: Interlibrary loan (ILL) is a free service where your local library borrows a book from another library — often across the state or country — on your behalf, giving you access to titles far beyond your own library's shelves.
How to request one
Ask at your library's reference or circulation desk, or look for an "Interlibrary Loan" or "Request an Item" link on the library's website. You'll typically fill in the title, author, and (if known) ISBN, and the library's ILL staff take it from there.
How long it takes and what it costs
Most requests arrive within one to three weeks, though rare or distant items can take longer. The large majority of U.S. public libraries offer this completely free; a small number charge a nominal shipping fee for certain items.
What ILL can and can't get you
ILL works well for older, out-of-print, or highly specialized books, including many academic texts. It generally doesn't work for very new releases (most lending libraries won't loan out a hot new title), reference-only materials, or extremely fragile rare books.
Academic vs. public library ILL
College and university libraries typically offer faster, broader ILL access for enrolled students and staff, often including journal articles and academic databases in addition to books — worth using if you have access through a school.
Can anyone use interlibrary loan?
Yes, as long as you have an active library card in good standing with a participating library.
Is there a limit to how many books I can request?
Most libraries cap active ILL requests (often 3–10 at a time), shown on the request form or by asking staff.
What if the book I want isn't available anywhere?
Ask your librarian about purchase requests — many libraries will buy a copy for their own collection if enough patrons request the same title.