Describes the evolution of the library control system at the Ohio State University library from a circulation control system to a full online catalog with subject access and authority control. The needs of users which prompted the development and possible future enhancements are discussed. (CLB)

Describes the design and operation of a prototype online catalog; reviews research which evaluated the system in terms of types of searches and success rates; and offers suggestions for enhancing subject access, including automatic stemming, synonym tables and cross-reference lists, and relevance feedback mechanisms. (CLB)