This report presents statistical pictures of Illinois Public Libraries during the fiscal year 1988-1989. The information comes primarily from the Illinois Public Library Annual Report forms. In addition, text has been included that describes how a library or library system can utilize these statistics. Three sections divide the publication. Section I presents facts about Illinois public library operations, use, resources, and finances. Section II describes statistical averages and percentiles for libraries which provide direct service and which serve populations of different sizes. Selected aspects of library operations are listed for individual libraries, and are provided in summary form for each population group. Charts highlight trends at the end of this section. Section III describes statistical averages and percentiles for libraries providing direct service with membership in one of Illinois' 18 multi-type library systems. Selected aspects of library operation are listed for individual libraries, and are provided in summary form for each library system. Charts that compare the individual systems are included in this section. Concluding the report is a copy of the Illinois Public Library Annual Report form. (MAB)