University of Michigan based researchers Neal Wiggermann and W. Monroe Keyserling conducted an experiment to investigate the effects of "anti-fatigue" mating on the perceived discomfort and weight shifting during prolonged standing. Their results are of great interest to ergonomists and employers seeking to reduce discomfort related to long duration standing. This article reviews the state-of-the-art understanding of the relationship between floor surface and standing discomfort and concludes with applicable recommendations for selecting anti-fatigue mats.