This joint project between the Brewers Association and the American Society of Brewing Chemists (ASBC) is designed to deliver basic quality methodology to attendees. Fermentation control is fundamental to brewing at any scale; yeast health and concentration have a profound impact on fermentation performance and flavor profile. This presentation will provide an in-depth explanation and demonstration of the simple and low-cost ASBC method used to determine cell count, viability, and vitality with a microscope, hemocytometer, and commercially available dyes.