This paper provides information on library services in Wisconsin, with a special emphasis on public library systems. The first section describes how library services are organized and administered, including municipal and county libraries, library systems, and the state Department of Public Instruction's Division for Libraries and Community Learning. The second section discusses how public libraries are financed, including municipal funds, county funds, state funds, federal grants, and other income; two tables present operating income for public library services and library system funding for 1997. The final section examines the formula used to distribute state aid to public library systems, including service requirements, formula factors (area, expenditures, population), and a sample aid calculation; two tables present state aid to public library systems for fiscal year 1997-98 and public library system aid for fiscal years from 1988-89 through 1998-99. A list of Wisconsin public library systems and their member counties is appended. (AEF)