OCLC Non-Supplier Locations
We always appreciate when you have made the effort to check the worldwide holdings of an item you need, and provide us with the OCLC accession number when submitting your ILL request. However, I would like to mention a few caveats related to the actual availability of materials that are recorded in the WorldCat database.
When you click on the Libraries worldwide that own item link within an OCLC bibliographic record, a list of library locations will appear, normally organized alphabetically by state but with Ohio appearing at the top, then Canadian and other international locations following. It used to be (if memory serves me correctly) that the status of a potential lender was indicated in the public view as follows -- uppercase OCLC symbols (or capitals in blue, underlined) signified supplier libraries, while lowercase OCLC symbols (or capitals in black, not underlined) indicated non-suppliers. The ILL staff view still retains this feature, so we are still able to immediately ascertain which libraries are most likely to supply materials through interlibrary loan.
Unfortunately, in the current public display this feature no longer persists (if it ever was there to begin with), and you as users are not able to make this distinction as are library staff. In fact, you may be led to believe that all listed locations for a particular item are potential suppliers, since all their symbols appear virtually the same (i.e., capitals, in black). Though it is not so easy for you to determine this any more, a helpful feature is still available. A great number of holdings locations also provide links to the institution libraries' online catalogs on their entry lines (though some of these may currently turn out to be broken as they haven't been updated). Those good links that exist may take you directly to the catalog entry for the particular item for the bibliographic record, or possibly only to the online catalog main search page or the library's main page. If you successfully reach a catalog record for your item at a particular library, the status and availability is usually indicated (e.g., whether item is non-circulating or currently checked out).
Finding a library catalog entry that shows available materials, however, is still not a guarantee that the institution is a potential lender, although it usually is a good indicator. The status of 'non-supplier' in an OCLC member's policy statement implies that they cannot receive requests through OCLC's ILL subsystem, our primary mechanism of operation. A library can list itself as a 'non-supplier' in one of two ways: permanently, as a matter of policy, or temporarily, according to a scheduled closure (holiday break, between academic sessions, re-location down-time, etc.). Also, OCLC libraries marked as supplier institutions can still act as virtual non-suppliers in specific circumstances, by setting up active deflection policies. These locations may choose not to lend outside their own consortium group, or may not loan certain material types (e.g., audio-visual or other special media, archival materials or items over a certain age, books that are deemed too new to loan externally).
Although there is no way now for public users to ascertain the supplier status of OCLC institutions, the following may serve as a rough guide. Most public and academic libraries in the United States and Canada will normally be suppliers, while a good deal of special libraries (corporate, private medical, museums, law firms) are not. Major research libraries in the United Kingdom and continental Europe often are suppliers, but many academic libraries in those places are not. Most libraries in Asia, Latin America, and elsewhere are non-suppliers, though a few academic libraries in Japan are. Several major academic libraries in Australia and New Zealand tend to be suppliers, as well. This is not a hard-and-fast set of rules, and is by no means exhaustive, but is just meant to give a rough approximation of what could be expected from various sources.
As obtaining materials on interlibrary loan from non-suppliers goes, the fact that they do not accept requests through the automated system in place that OCLC provides means that it is much more difficult than usual to borrow from them, if it can be done at all. Many such institutions simply are non-circulating collections, and often will not agree even to provide complete or partial reproductions. Those that will agree to offer interlibrary loan services require the use of mechanisms other than OCLC to receive request transactions. Submitting requests by these means is usually much more time-consuming, and the turnaround time for responses and receipt of materials is much longer than in more routine cases.
OCLC is not the whole story in the business of interlibrary loan, of course, but it is the principle workhorse for us and many other institutions. Libraries that do not act as suppliers through OCLC frequently are those with rare or esoteric collections, and it is in cases where these types of materials are required that our efforts will be protracted. Please be reassured that we still work outside this resource when absolutely necessary to get our users the materials they need. We just want you to be aware that, even though we try to be expeditious in the majority of our services, there are still circumstances beyond our control that put us into a 'holding pattern' (such as needing to borrow a foreign thesis during an academic session break). Your patience, understanding and consideration in such cases it always greatly appreciated.