A sobriety checkpoint demonstration program was conducted in the State of Tennessee between April 1994 and March 1995. Prior to this period, the state typically conducted 10-15 checkpoints on an annual basis. During the experimental checkpoint demonstration period, a total of almost 900 checkpoints were conducted involving close to 150,000 drivers checked and resulting in almost 800 arrests for driving under the influence (DUI) or driving while intoxicated (DWI). The checkpoint program was highly publicized over TV, on the radio and in the newspapers throughout the state. Surveys of drivers throughout the state indicated awareness of the enforcement program An interrupted time series was used to analyze the traffic safety impact of the program The results showed a 17% reduction in the number of drunk driving fatal crashes that would have occurred without the checkpoint program.