Regions and gates can be made to better separate and analyze populations of interest. Furthermore, on the basis that the dyes used to stain cells have overlapping emission spectra, the compensation is normally made to reduce interference. While basic instruments may only permit the simultaneous collection of two or three fluorescence signals, the more complex and expensive research instruments mean that it is possible to obtain more than 14 parameters (Winson & Davey, 2000; Chattopadhyay et al., 2008) depending on the laser equipment utilized. Selection of the lasers will depend on the range of wavelengths needed for the excitation of the selected fluorochromes