In February 2005 residents of Edinburgh in Scotland, UK, were given the opportunity to vote in a referendum on the introduction of a road user charging scheme, which had been in development for almost a decade. The public voted against the scheme by a ratio of 3:1 and it was consequently abandoned. The objective of this research was to determine the principal factors responsible for the public's overwhelming opposition to the scheme. A postal self-completion questionnaire was distributed to 1300 randomly selected households along a transect from central to south Edinburgh. The 368 completed questionnaires returned were analysed to assess the influence of several factors on the way respondents voted in the referendum. Car use was shown to be the principal determinant of voting behaviour, with car owners strongly opposing the scheme and non-car owners only weakly supporting it. The public's limited understanding of the scheme increased the strength of the opposing vote. Further, the public were largely unconvinced that the scheme would have achieved its dual objectives of reducing congestion and improving public transport. The findings suggest that more attention should have been paid to designing a simpler, more easily communicated scheme and convincing residents, particularly public transport users, of its benefits.