PDQ is a joint project of the Royal Canadian Mounted Police and the Federal Bureau of Investigation, and it is funded by the U.S. Justice Department's National Institute of Justice (NIJ). Now in its fourth year, PDQ contains more than 9,000 paint systems that encompass just over 33,000 layers in a database that can differentiate vehicles based on the paint's chemistry, color, and the number and sequence of layers. PDQ responds to paint inquiries that supply findings from microscopic examination, infrared spectroscopy, and topcoat color verification. It also uses the Munsell numbering system to assign a color to undercoats. PDQ contains paint information for most domestic and foreign manufacturers and most of the vehicles marketed in North America after 1973. In the United States, PDQ is used by city, county, and State laboratories. In exchange for use of the database, agencies are required to collect 60 street samples of vehicle paints annually. The database relies on vehicle manufacturers for samples as well; street samples provided by participating agencies help to check the information and the samples provided by the manufacturers. This article describes the procedure for enrolling in PDQ and presents a brief case history of how PDQ was instrumental in solving a hit-and-run accident in Washington State.