Granular overlays have been used by the Washington State Department of Transportation (WSDOT) for about 30 years. Since the mid-1980s and along with the full implementation of the WSDOT Pavement Management System (WSPMS), WSDOT has been interested in examining the performance of granular overlays. It is felt by WSDOT that the performance of this rehabilitation treatment is better than one might reasonably expect. Further, past practice in Washington State occasionally required that the preexisting surfacing (often several bituminous surface treatment (BST) layers) be scarified prior to placement of the crushed rock layer. This summary report overviews the study and conclusions.