The acceptance of policies to reduce negative externalties of transport by lowering the speed of car drivers. Respondent has disposal of means of transport / drivers license / number of kilometres driven per year, subdivision in type of use / buying a car: important aspects of car / type of present car / number of fines for driving to fast last year / own speed compared to speed of others / feelings of unsafety caused by speed of others / perception of speed on roads with maximum speed of 120, 100, 80 and within the built-up area/ acceptability of graduations of exceeding maximum speed / frequency of respondents own exceeding / lowering maximum speed on Dutch roads is useful / reasons for ( not ) exceeding maximum speed / respondent or other member of household had a severe traffic accident in the past / under certain circumstances for-against obligatory use of speed delimiters / ( dis- ) advantage of speed delimiters. Background variables: basic characteristics/ residence/ income/capital assets/ education