This report responds to the need for North American libraries to provide computer support for multiple subject lists or controlled vocabularies as they automate separate catalogs using specialized thesauri for certain subject areas, materials, and audiences in addition to their main library catalogs. The focus of the report is the integration of the areas of thesaurus management, subject authority control, and subject searching in a system where the thesaurus is maintained as an authority file, and is indexed and linked to bibliographic records for searching. Divided into five major sections, the report provides: (1) an overview of multiple thesauri and computer support for controlled vocabularies; (2) a discussion of thesaurus management, including computer support for relating multiple thesauri; (3) a review of subject authority control, including background information and descriptions of seven systems, i.e., ORION, WLN computer system, DOBIS as implemented by the National Library of Canada, UTLAS, Geac bibliographic processing system, Northwestern Online Total Integrated System (NOTIS), and Carlyle systems TOMUS; (4) a discussion of subject searching which includes online catalog search features and approaches to retrieval of multiple subject vocabularies; and (5) a description of computer support for multiple thesauri at the Library of Congress, including online subject authority control and online subject searching. A 17-item bibliography is provided. (CGD)