Results indicated that of the 781 drivers tested at Random Breath Testing (RBT) sites, 3.5 percent (27 participants) tested positive for at least 1 illicit substance, most commonly cannabis (13 participants) followed by amphetamine substances (11 participants). Other findings revealed that cannabis was the most commonly self-reported drug combined with driving and that individuals who tested positive for any type of drug were also more likely to report the highest frequency of drug driving. Comparisons of the detection rates for drug driving versus drink driving indicated that drug driving was detected at a higher rate (3.5 percent) than was drink driving (0.8 percent) in Queensland. The findings thus suggest that drug driving is a relatively common occurrence in Queensland. The findings also confirm the utility of using self-report data on drug driving due to a high convergence between those who reported illicit drug use and positive RBT tests. Future research into the problem of drug and drink driving in Queensland is warranted and will aid the Police Services in developing effective countermeasures and enforcement policies. Data were drawn from oral fluid samples collected from 781 drivers by the Police Services. Participants volunteered for participation at RBT sites in a large regional area of Queensland and were asked to self-report any drug use prior to the RBT testing. Drugs included in the testing were cannabis, amphetamine type substances, heroin, and cocaine. Tables, notes, references