Originally Z39.50 was designed to help with searching very large bibliographic databases like those of OCLC and the Library of Congress. Today Z39.50 is used for a wide range of library functions that involve database searching, from cataloging to interlibrary loan to reference. With the rapid growth of the Internet, the Z39.50 standard has become widely accepted as a solution to the challenge of retrieving multimedia information including text, images, and digitized documents. Z39.50 is being used to access, for example, museum data, government information, and geospatial data. It can also be used to search the online databases and CD-ROMs that vendors develop according to a variety of design schemes. Without having to learn each system, users can search those databases with a single Z39.50 client, even though each uses a different hardware and software configuration, stores different types of data, and has different internal search logic.

Resource sharing
Z39.50 can encourage resource sharing on a broad scale. In the library community, for example, Z39.50 supports

  • broadcast searching of library catalogs located on the Internet anywhere in the world,

  • interlibrary loan through Z39.50’s standardized approach for delivering holdings information, and

  • online item ordering and document delivery

Increased productivity
Because the search interfaces of different systems are transparent,
users no longer need to master how to use each database, avoiding a potentially steep learning curve. Staff training time can be reduced for functions that require database searching, such as cataloging,
acquisitions, and interlibrary loan. Easier access to electronic resources reduces all users’ time spent in searching for relevant

Niso Press (2002). Z39.50 a primer and the protocol. Date of retrieve 1/8/2011.
Retrieve from