A study to be made with computer-based circulation data of the non-use and use of a large academic library is discussed. A search of the literature reveals that computer-based circulation systems can be, but have not been, utilized to provide data bases for systematic analyses of library users and resources. The data gathered in the circulation system will be of particular value in two areas: identifying the non-users of a library and the areas of non-use and testing, and demonstrating the use of computer-based circulation data files as the data base for studies that would improve services and provide decision-making aids. The study methodology would involve the comparisons of the circulation transaction files and the borrower address files to produce two areas of investigation, use and non-use. A variety of information would be gathered about each group. (Author)