This study presents a detailed evaluation of the impact and effectiveness of Title I of the Library Services and Construction Act (LSCA), a federal program designed to assist state efforts to develop and improve public libraries, and examines the policy implications of these results as they relate to the future of federal involvement in public libraries. It presents the history and background of LSCA, study methodology, the uses of LSCA funds, factors affecting these uses, changes in library services and organization resulting from LSCA, effects on the coverage and accessibility of public library services, problem areas and future directions, and major findings and their implications. Statistical data and comparative analyses are presented in 80 tables, and the appendices provide details of the research methodology, selected references, a glossary of terms, supplementary tables, advisory panel members, and data collection instruments. (RAA)