A major problem in assessing the impact of drugs on driving is the fact that the driving variables being measured can vary signi¨cantly. In studies being reported, the basic parameters being assessed are o±en not comparable due to a lack of standardization in the ¨eld. Due to these methodological di¥erences in the ¨eld researchers have tried to develop a consensus on research standards that will increase comparability between drug e¥ects measured in laboratory tests, driving simulators, and actual driving tests. Such consensus reports have most notably been issued by the International Council on Alcohol, Drugs and Tra¬c Safety (ICADTS). A ¨rst consensus report was issued by the ICADTS working group on “the standardization of experimental studies of drugs and drivers” (1999). še second consensus report appeared in 2007 by an ICADTS working group on “illegal drugs and driving”. Excerpts from these consensus reports related to the operationalization of driving tests will be given below. Full copies of these reports can be found at https://www.icadts.org.