A new study confirms that the Federal Motor Carrier Safety Administration’s Safety Measurement System (SMS) is more effective at identifying commercial bus and truck companies of all sizes for targeted enforcement than the system it replaced. Researchers analyzed the association between historical carrier data and future crash involvement by taking two years of pre-SMS safety data for a subset of carriers, running it through the system’s algorithm, and then following those companies’ crash records for eighteen months. Results show that the companies the SMS would have identified for interventions, such as roadside inspections, warning letters and on-site investigations, had a future crash rate of more than double the national average. In addition, 79 percent of the carriers that SMS would have ranked as high risk in at least one of the seven safety categories it monitors, had higher future crash rates compared to those it would not have identified. SMS is a component of the agency’s Compliance, Safety, Accountability program, which was launched in 2010 to identify and prioritize motor carriers that pose the highest threat to public safety for enforcement interventions. The study was conducted by the Volpe Center and peer-reviewed by independent experts. The full report is available athttp://csa.fmcsa.dot.gov/Documents/CSMS_Effectiveness_Test_Final_Report.pdf.