Flow Cytometry Project Summary/Abstract The primary purpose of the Flow Cytometry Module is to provide Principal Investigators with a centralized service for cell counting, fluorescent-activated cell sorting (FACS) to obtain s t e r i l e viable populations of cells according to specific cellular markers, phenotypic characterization of cells, and biomarker detection. Such a service makes expensive equipment for FACS sorting and analysis available to researchers. In addition, the module provides full-time technical support for the maintenance and calibration of the equipment, helps develop experimental procedures, assists with analysis and interpretation of data, and centralized internet access to the database.