TRB’s National Cooperative Highway Research Program (NCHRP) Synthesis 382: Estimating Stiffness of Subgrade and Unbound Materials for Pavement Design explores the significance of the resilient modulus property, various methods of determining this property of subsoils and unbound bases, and the application of this parameter in the mechanistic-empirical pavement design guide. Report located at https://www.trb.org/news/blurb_detail.asp?id=9866.