One means to lower the number of commercial vehicle driver errors is to improve driver performance through onboard monitoring systems, coupled with appropriate feedback to the driver. This Onboard Monitoring and Reporting for Commercial Motor Vehicle Safety (OBMS) project was a Federal Motor Carrier Safety Administration Cooperative Agreement with Caltrans. The OBMS project resulted in an implemented and tested prototypical suite of hardware on a Freightliner Century Class tractor. Two types of feedback are provided by the system: real-time and off-line. The real-time feedback provides warnings of an imminent threat (such as a forward collision or lane departure) and informs the driver that an incident has triggered a recording for the off-line system. The off-line feedback provides a summary of the trip, including recorded incidents, which can be reviewed by the driver and management. Comparison of the off-line summary may be made across drivers and across time to allow for better management of commercial vehicle operations.