In order to find reliable methods of ascertaining quality in library service, three public libraries in the Chicago area were assessed using the Rutgers "Performance Measures for Public Libraries." The Rutgers study can reveal the needs and characteristics of library patrons, and may itself be instrumental in increasing patronage. It also may be used as an effective idea generator. Most importantly, the data gathered in this study can also aid management in the decision making and in the formulation of library budgets. (DS)