Many cities have seen public support for congestion charges increase substantially after charges have been introduced. Several alternative explanations of this phenomenon have been suggested, but so far little evidence has been available to assess the relative importance of these explanations....

This study revisits some of the key project participants and archive data, to provide a deeper understanding of what were the major cost drivers and whether it can be lower in future installations. The approach taken is to emphasise understanding of the particular circumstances rather than...