TRB’s Transportation Research Circular E-C124: Practical Approaches to Hot-Mix Asphalt Mix Design and Production Quality Control Testing explores the state-of-the-practice for Superpave mix design and specification, including a summary of changes made to the Superpave mix design procedure as a result of National Cooperative Highway Research Program research findings, American Association of State Highway and Transportation Officials' Expert Task Group recommendations, and individual state experience. The report also examines other tools for mix design and evaluating hot-mix asphalt during production that are relatively simple and implementable.