Library of Congress

Cataloging Distribution Service

The Library of Congress > Cataloging Distribution Service > Subject Heading Authority Control

Back to Product Categories

Help in all areas of subject access is available through these tools. Published in various formats, the major subject headings authority tools listed here are included in either Classification Web (http://www.loc.gov/cds/classweb) or Cataloger's Desktop (http://www.loc.gov/cds/desktop). Both are web-based subscription services and both offer free 30-day trials.