Regional Interlibrary Loan: An Old Idea; A New Tool and a New Dimension.

Use of a new type of computer generated regional numerical union catalog in Louisiana is evaluated. The catalog, called Louisiana Numerical Register (LNR), contains 550,000 titles and 1.2 million locations. Total develop mental costs and prorated costs of interlibrary loans are shown to be less than what the total costs of titles successfully searched would have been had they been purchased instead of loaned. Contributors to the LNR were seven teen academic libraries, two medical libraries, the Louisiana State Library, and the New Or leans Public Library. A stipulation of the sup porting agency (Louisiana State Library) was that titles listed would be freely available to all types of libraries in Louisiana. Though aca demic libraries contributed 79 percent of the titles, they made only 30 percent of the searches, while noncontributing libraries made 68 percent of the searches. The number of ti tles successfully searched ran consistently higher than 50 percent. Parish and public li braries successfully found 57 percent of titles searched, and academic libraries, 39 percent. To distribute the burden of interlibrary loan, libraries agreed always to borrow from the smallest library owning a title. Implications of the new tool: similar registers in another state have been inspired by the LNR; published holdings may influence buying policy; unit costs are vastly reduced; updates are inexpen sive; every library in the region may own a copy; the feasibility of public and academic library cooperation has been demonstrated; borrowing from the smallest library distributes interlibrary loan more evenly.