Ground penetrating radar (GPR) is a noninvasive, continuous, high-speed tool that has been used to map subsurface conditions in a wide variety of applications. Many of these applications are well suited for evaluation of highway systems. GPR is basically a subsurface "anomaly" detector, as such it will map changes in the underground profile due to contrasts in the electromagnetic conductivity across material interfaces. This report will give the local engineer a brief overview of GPR equipment, use and applications. It will help the engineer understand the potential GPR applications for use on local roads, assist in determining what situations or site conditions that GPR is appropriate, and where it is not.