The roadside Inspection Selection System (ISS) was developed in response to a 1995 congressional mandate that called for the use of prior carrier safety data to guide the selection of commercial vehicles and drivers for roadside inspections. The program was developed in part by the Federal Motor Carrier Safety Administration (FMCSA) of the U.S. Department of Transportation. As ISS has developed, FMCSA's Performance and Registration Information Systems Management (PRISM) program has also been evolving. One objective of PRISM is to identify relatively unsafe carriers by assigning Safety Status Measurement System (SafeStat) scores and also encouraging those drivers to improve their safety performance or risk losing registration privileges. SafeStat was designed to prioritize carriers for monitoring and compliance reviews, but ISS was designed to prioritize carriers for roadside inspection. Both algorithms, however, use similar data to define a relatively unsafe carrier. It would be advantageous therefore to have a single uniform rating system for all FMCSA programs. This research briefly describes the PRISM and SafeStat algorithms; discusses the integration of the SafeStat algorithm into ISS; and presents conclusions on the initial testing of the resulting system, ISS-2. An analysis of over 213,000 roadside inspections reveals that ISS-2 is as effective as the original ISS in meeting the goals for which it was designed. It successfully identifies and prioritizes for roadside inspection the vehicles and drivers of carriers with poor prior safety performance, as well as those with few or no previous inspections. In addition, safety inspectors who have tested the system say they are pleased with the new algorithm and its added features.