Police Services in a number of Australian states have indicated random roadside drug testing will be implemented to target drug driving. This paper outlines research conducted to provide an estimate of the prevalence of drug driving in a sample of Queensland drivers. Oral fluid samples were collected from 781 drivers who volunteered to participate at Random Breath Testing (RBT) sites in a large Queensland regional area. Illicit substances tested for included cannabis (delta 9 tetrahydrocannibinol [THC]), amphetamine type substances, heroin and cocaine. Drivers also completed a self-report questionnaire regarding their drug-related driving behaviour. Samples that were drug-positive at initial screening were sent to a government laboratory for confirmation. Oral fluid samples from 27 participants (3.5%) were confirmed positive for at least one illicit substance. The most common drugs detected in oral fluid were cannabis (delta 9 THC) (n = 13) followed by amphetamine type substances (n = 11). A key finding was that cannabis was also confirmed as the most common self-reported drug combined with driving and that individuals who tested positive to any drug through oral fluid analysis were also more likely to report the highest frequency of drug driving. Furthermore, a comparison between drug vs drink driving detection rates for the study period revealed a higher detection rate for drug driving (3.5%) vs drink driving (0.8%). This research provides evidence that drug driving is relatively prevalent on Queensland Roads. The paper will further outline the study findings and present possible directions for future drug driving research.