The National Agricultural Library was created as the departmental library for the U.S. Department of Agriculture in 1862 and became a national library in 1962. One of four national libraries of the United States (along with the Library of Congress, the National Library of Medicine, and the National Library of Education), it is also the coordinator for a national network of state land-grant and U.S. Department of Agriculture (USDA) field libraries. In its international role, the National Agricultural Library serves as the U.S. center for the international agricultural information system, coordinating and sharing resources and enhancing global access to agricultural data. The National Agricultural Library's collection of over 3.3 million items and its leadership role in information services and technology applications combine to make it the foremost agricultural library in the world.
The National Agricultural Library houses several specialized information centers, which provide access to comprehensive and essential information resources focusing on the specific aspects of agricultural subjects. In addition to the general reference services available at NAL, each center offers Internet access to resources enhancing information availability and dissemination. The centers have staff available to serve customers on-site as well as by phone, fax or email. The Information Centers at the National Agricultural Library include: