Initiated by the Council on Library Resources, this study assessed the current level of retrospective conversion and explored the primary issues that need attention if libraries are to convert their bibliographical files to machine-readable form. Data were obtained from a literature review, contact with a number of libraries currently engaged in retrospective conversion, and information gathered from three major American utilities, several service centers, and regional networks. The report is organized in four major sections: (1) an overall framework for analyzing retrospective conversion, including a definition, a brief summary of past efforts to develop a coordinated strategy, a description of current activity, and a look at future developments; (2) major approaches to and library strategies for retrospective conversion; (3) the economics of retrospective conversion and the quest for a national database; and (4) five strategic options for a systematic approach, recommendations for a national strategy, and a proposed implementation strategy. A selected bibliography and a brief description of the Association of Research Libraries (ARL) and Research Libraries Group, Inc., National Collections Inventory Project are included. (THC)