High speed and an aggressive style of driving are major risk factors for serious traffic accidents. Consequently, frontline emergency medical services vehicles have an increased collision risk. We report on two studies designed to modify the risk-taking behaviour of emergency medical services drivers. In the first study, we compared the travel intervals for a second tier unit using two different types of vehicles. We found that the replacement of a sports estate by an ambulance, which can be considered more or less as a change from a speedy and aggressive style of driving to a cautious style of driving with respect for the speed limits, resulted in an increase of the travel interval of only 10-20%. In the second study we found that the installation of a 'black box' in an emergency medical services vehicle, combined with well-defined guidelines for the drivers and a close monitoring system, provides fair but still not optimal results with regard to maximum speed and the occurrence of harsh braking events. Despite some limitations in the study designs, we conclude that for second tier units only a small amount of time is gained by high speed and an aggressive style of driving. Furthermore, we are convinced that a 'black box' is a good tool to modify the risk-taking behaviour of emergency medical services drivers.