Abstract
Before the re-unification of Germany a zero BAC-limit was valid in the new federal states; after re-unification the legal limit of the old states (0.08 per cent BAC) was applied throughout Germany. The empirical evidence requiring lowering the limit is summarized and demonstrates legislation and action taken in other countries to enhance traffic safety through prevention and control of DUI. Psychological reasons for the difficulties of drinking drivers to control their driving and driving interrelated with public opinion and legislation are presented. It is argued that primary and secondary prevention are linked to legislative signals, such as lowering the limits.