ABSTRACT The Case Comprehensive Cancer Center Cytometry & Imaging Microscopy Core provides access to cytometry, cell sorting, and microscopic instruments and services to the campus of Case Western Reserve University (CWRU) and the wider Cleveland area. This core has been in continuous existence since 1985 and funded by the NCI through a P30 grant since 1987. In recent years, the core has formed cooperative agreements with the Case Center for Aids Research (CFAR) Immune Function Core, and the Digital Imaging Microscopy Core of the Cleveland Clinic Lerner Research Institute to leverage complimentary expertise and reduce instrument duplication. Within the past four years, over 500 users from 195 laboratories have used the core. Of these, 42 NIH funded investigators need continuous cell sorting support. The core has two cell sorters; the main instrument is aged BD Aria with limited laser/parameter capability, and the second sorter is a Sony Reflection which is obsolete, operationally unstable (and therefore not safe for BSL II work), and has limited multiparameter work. Because of the growing need for sorting per se, sorting of viable human cells, infected cells, or other BSL II samples, and increased need by investigators with fragile and/or time-sensitive samples, we need to replace the Reflection with a modern cell sorter that matches the capability of our analytical instruments. We propose to acquire a BD Influx equipped with a laser/pmt/filter set up that mimics our LSR II and Fortessa instruments and additionally has microparticle sorting capability to sort virus, exosomes, and high throughput sorting of Circulating Tumor Cells. This will provide stable, safe, and flexible sorting capability and sufficient capacity for this large, busy core. This BD Influx will shore up failing systems as well as greatly expand the capacity and cutting edge research being performed in our area.