Beginning this annual report is a letter to the OCLC membership from OCLC President and Chief Executive Officer, K. Wayne Smith. Statistical data are then presented in tables and/or graphs for OCLC programs and the system's financial status for fiscal years 1990/91 and 1989/90; the growth of the OCLC Online Union Catalog from 1971-1991 in terms of LC-MARC (Library of Congress-Machine Readable Cataloging), LC-created/member-input, and member-input records; and the number of participating member libraries. Information about OCLC's new, modular technological platform is then provided, including the new telecommunications network, the new online system (PRISM service), and the new reference system (EPIC and FirstSearch services). Strategic information alliances that OCLC is entering into with other organizations are also described. It is noted that these alliances will provide new products and services in such areas as preservation, electronic publishing, and document delivery. A month-by-month review of OCLC's major accomplishments during the fiscal year is followed by an overview of OCLC's services to libraries from 1972 to 1991, which is presented in a chronological table. Concluding the report are the 1990/91 financial report and the names of the OCLC Board of Trustees, officers, users council delegates, and network members. (MAB)