The first professional librarian to head the Cataloging Department at the Coleman Karesh Law Library, for 25 years Diana oversaw the changes that took place in bibliographic description and classification of legal materials as libraries undertook the transition from manual to digital information retrieval. During her tenure here, the Library of Congress completed publication of classification schedules for the laws of all nations, which necessitated upgrading and reorganization of local records and materials.  She joined the Thomas Cooper librarians in planning and adding USC's holdings to the national online database. At various time she sat on the USC Faculty Senate and on committees of her national professional association, the American Association of Law Libraries (AALL). In the Southeastern Chapter of AALL she was elected Treasurer and also served as Secretary and as Distribution Manager for the newsletter.

Diana Osbaldiston worked at USC School of Law from April 16, 1977 to June 30, 2002.