Laser scanning cytometry (LSCM) automatically measures laser excited fluorescence at multiple wavelengths and light scatter from cells on slides that have been treated with one or more fluorescent dyes to rapidly determine multiple cellular constituents and other features of the cells. This chapter describes a specific laser scanning cytometer, the LSC that can use these techniques perfected for flow cytometry (FCM) to provide data comparable to FCM. Because it is microscope based and measures cells on the surface of a slide, records position of each cell on the slide, and has higher resolution, it can provide a number of benefits that may make it a more suitable cytometer for certain applications. LSCM is not comparable to confocal microscopy. Because LSCM must uniformly illuminate cells throughout their volume to obtain accurate whole cell constituent measurements, its optical components are designed to be nonconfocal. LSCM uses large field depths, and confocal microscopy emphasizes short field depth to provide detailed images at a narrow depth focal plane through each cell that is imaged. Additionally, LSCM is designed to automatically measure large heterogeneous populations of cells, unlike the detailed single cell analysis, for which confocal microscopy is most useful.