It is proposed that the National Flow Cytometry and Sorting Research Resource (NFCR) continues to be made available to biomedical scientists from across the country. In addition the NFCR will develop, upgrade, and institute new technologies on existing instruments that are needed to solve biomedical and clinical research problems. The NFCR was established on July 1, 1982 and has gained momentum as a developmental and applications facility that has provided unique capabilities to a large number of collaborators and users from around the county. New "state-of-the-art" flow systems will be developed which will have unique capabilities. We intend to focus upon: chromosome image analysis and high speed sorting, multiparameter flow cytometry for cell biology related applications, and new data analysis capabilities. Existing capabilities will be continually upgraded to maintain their forefront status. These instruments will be used for a series of user and collaborator generated studies and applications. Several on-site experts will work directly with these individuals to elaborate new and demanding techniques, and to train them in the use of the instrumentation. Techniques include phase sensitive detection of time resolved fluorescence, kinetic measurements, solution calibration of fluorescence, elimination of multilaser excitation interference, and Fourier transform flow cytometry. Research fields will include: immunology, cell biology, tumor biology, molecular biology, radiobiology, and genetics. The procedures and methodologies available at the NFCR and its activities will be broadly disseminated through the Los Alamos Flow Systems Newsletter, publications, national meetings and by close cooperation with DRR personnel.