Given that no library can afford to purchase, house, and preserve every information source that its patrons might need, information resource sharing, in the form of interlibrary loan (ILL) and document delivery (DD), has become a core library service. Of course, information sharing is an activity that librarians must balance with other equally essential responsibilities, such as preservation concerns, cost considerations, and the maintenance of circulating collections for local patrons. Still, despite the inevitable tensions inherent in these somewhat contradictory functions, libraries and library organizations, such as OCLC, RLG, and ALA, have long reigned as the dominant players in this important arena. In fact, OCLC alone fills an ILL request every four seconds (OCLC). Now, however, libraries find themselves facing new and increased competition from a variety of web-based information services. Although only Google is rich enough even to attempt to compete with libraries on all fronts, other relevant ventures include Amazon.com and BarnesandNoble.com (which sell books and other materials), Ingenta and CISTI (which deliver articles), MSN and Yahoo (which provide content and search services), and Netflix (which rents DVDs) and Bookswim.com (which uses a Netflix model to rent books).
