This document is a manual designed to improve library services to young adults. Information is divided into three parts: (1) "Applying the Planning and Role Setting Process to Library Services for Young Adults"; (2) "Evaluating the Results: The Measurement Process"; and (3) "The Output Measures." Part 1 discusses the Public Library Association planning and role setting process; organizational considerations; conducting the needs assessment; developing a plan for library service to young adults; and sources for additional information. Part 2 covers measurement and the planning process; managing the measurement process; collecting and analyzing the data; interpreting the results; using qualitative evaluation methods; acting on the results; and sources for additional information. Part 3 includes definitions and describes measures of the following: library use, materials use, materials availability, information services, programming, community relations, and youth participation. Appendices provide a sample interview and focus group questions, and blank work forms. (AEF)