Foliar fungicide applications have now become common in corn production, often applied in the absence of disease and in contrast to Integrated Pest Management recommendations. Farmers and County Agents need information to help them understand how fungicides should be used, and when they have optimum efficacy against corn diseases. The Extension corn pathologist at the University of Kentucky coordinates with other corn pathologists in the United States to create national corn fungicide efficacy tables to help farmers and others understand how individual fungicide active ingredients work against diseases. This multi-state effort was published as University of Kentucky Extension Publication PPA-49, and is accessed nationally at the Crop Protection Network website annually by over 80,000 unique users.