The Belgian Road Research Centre (BRRC) and its partner Institut Scientifique du Service Public (ISSeP) performed a four-year research project into the use of Ground-Penetrating Radar for pavement surveys. The essential aim of this project was to develop methodologies to improve GPR data collection and interpretation for road surveys. This included the estimation of layer thickness, the determination of homogeneous zones, and void detection. Results were obtained from experiments with GPR both under controlled conditions and on roads. The knowledge and experience acquired during the first part of this project provided the basic material for a BRRC publication “Methodologies for the Use of Ground-Penetrating Radar in Pavement Condition Surveys”, which is available on the BRRC web site. The methodologies were applied to a road section to be rehabilitated. The results of the project are presented in a research report published in October 2017.