Motorists driving the wrong way on divided roadways has been an area of concern for over 50years. However, little is known about the nature of wrong-way crashes on divided highways. Thus, the research team conducted exploratory and statistical analyses to assess the effects of median width and select traffic control devices upon wrong-way crashes on high-speed divided highways. The exploratory analysis revealed that most of the wrong-way crashes on high-speed divided highways resulted in serious injury and happened at night. More than two-thirds of the wrong-way crashes resulted from a wrong-way maneuver at an intersecting roadway where a median opening was present. The statistical analysis found numerous sites where the traffic control in the median opening did not fully comply with the Manual on Uniform Traffic Control Devices (MUTCD) with respect to treating the location as one or two intersections. There was also evidence from the statistical analysis that the 30-ft median width threshold may not be appropriate for distinguishing between one or two intersections. In addition, researchers were able to identify several traffic control devices that may be effective in reducing wrong-way movements on high-speed divided highways. The final effort of the project was to develop recommended MUTCD language for implementing the research findings. The recommended language includes a new method for distinguishing between divided highway crossings that function as a single intersection or two separate intersections, thereby eliminating the 30-ft median width threshold used in the current MUTCD.