The goal of this project is to develop economical, easily used microcomputer sleep software for the digitization, signal analysis, summarization, statistical analysis, and graphic presentation of sleep EEG. The software uses established techniques of period and amplitude analysis, which reflect the characteristics of individual waves more than spectral analysis does. The software will be immediately applicable to the following areas of biomedical significance: analysis of change of sleep patterns with aging, schizophrenia, depression, drug use, and sleep disorders including insomnia, narcolepsy, and sleep apnea. the target market consists of all sleep laboratories, both research and clinical, for use in sleep studies and in diagnostics. The software is designed to use standard, low-cost, high-performance microcomputer hardware, an IBM-AT compatible, with optional high capacity storage or high quality display. The use of modern software engineering techniques strengthens system reliability and simplifies future development. The primary goals of Phase II are to:integrate the older software components of the system with the new user interface and new components; improve the performance of the software; add several new features; expand the user help system; write complete user documentation; and test the software thoroughly.