This presentation will help consultants, Extension agents, growers, and other practitioners in potato-producing states to understand more about phosphorous acid and its use in potato post-harvest situations. Specifically, in this presentation, practitioners will learn the differences between phosphorus-containing compounds used in agriculture, what pathogens are controlled by phosphorous acid, and how to apply the material to potatoes entering storage. By the end of this presentation, practitioners should increase their knowledge of phosphorous acid and how to best use it in potato post-harvest situations for optimal disease control.