Find out about states' efforts to collect data on drug-impaired driving and discuss the National Highway Traffic Safety Administration's evaluation tool to help states combat drug-impaired driving. Driving under the influence of drugs-with or without alcohol-appears to contribute to crashes, but data is incomplete and inconsistent, making it tough to track the scope of the problem. Speakers include Timothy Kerns, Maryland Department of Transportation, and Staci Hoff, Washington Traffic Safety Commission.