The support for controversial policies in the area of transport often increases after real-world implementation. In this paper, we provide a comprehensive overview of the literature surrounding the implementation of controversial policies in transport, particularly in the context of road pricing. We then discuss various theories and mechanisms that contribute to an increase in support for such policies after real-world implementation. One significant factor is a change in attitude towards a policy. However, there are also other important factors, for example the utility experienced by people is not necessarily the same as the expected utility. In addition, people may be loss-averse relative to their reference point (often: their current situation). The disadvantages of a policy considered for implementation may be clearer than the advantages. Other factors discussed are the effect of the expected distribution of gains and losses, their magnitude, and perceptions of the processes being fair and competent. We then examine the implications of increased support after implementation, important lessons being that policymakers can anticipate growing support after implementation and that communication is key in the process of deciding on a controversial policy. In this regard, we propose that having a champion, or visionary, can be particularly effective in getting controversial policies accepted. Finally, we suggest avenues for future research.@en