Discusses the reasons and methods for retrospective conversion of library catalog data into machine-readable form. The need for standards is emphasized and suggestions are given for documenting local standards. Ideas are included for completing the conversion of a project done by a vendor, where some parts may have been overlooked. (Author/EM)

Reviews authority control as represented in the literature from circa 1900 to the present. Catalog codes and handbooks are examined; efforts to develop authority files are summarized; and consideration is given to impact of automation on authority control. A list of recommended readings is included and 46 references are provided. (Author/EJS)