The European Integrated Project DRUID (Driving Under the Influence of Drugs, Alcohol and Medicines) is a part of the 6th Framework Program, the European Community Framework Program for Research, Technological Development and Demonstration. The objective of DRUID is to give scientific support to the EU transport policy by providing a solid basis to generate harmonised, EU-wide regulations for driving under the influence of alcohol, drugs and medicine. This study is a part of Work Package 2, Epidemiology, of the DRUID project. The objective of the study is to assess the situation in Europe regarding the prevalence of alcohol and other psychoactive substances in drivers who have been injured/killed in traffic accidents. Part 1 of this report presents the general results of the hospital & killed driver studies. After a short introduction, the representativeness of the populations in the EU countries as well as the representativeness of hospitalised and killed driver samples are addressed. An overview of the non-response issues in the various countries is also included. Based on the toxicological findings, a general summary of the prevalence of drug use is given for the 9 participating countries. This is followed by a discussion and a conclusions part. Part 2 and 3 of this report include all the country reports. In this part more detailed information regarding study design, methods, representativeness of the sampling and results on a national level can be found.