Measuring the concentrations of asbestos in contaminated soils is challenging. Data are often highly variable. Variability in soil measurements has led to limitations in comparing results from sites nationally and difficulties in reproducing results, even from the same sites over time. The difficulties in collecting reproducible soil data limit the ability to extrapolate from concentrations in soil and compare to concentrations in air. This extrapolation is necessary if soil data are to be used in human health risk assessments. To address this substantial limitation of asbestos soil data, researchers from Environmental Protection Agency (EPA) regions and the National Exposure Research Laboratory are conducting a series of efforts to advance the use of data that are collected, processed, and analyzed using the most reproducible methods. These soil data, collected from a variety of sites across the country, will be compared to air data from activity-based sampling in an attempt to establish a quantitative relationship between asbestos soil concentrations and airborne fiber concentrations. This research plan summary provides an update on the EPA efforts under way and the challenges that lie ahead.