Lessons from the Stockholm congestion charging trial

The Stockholm congestion charging trial in 2006 resulted in large effects on traffic volumes and congestion. During the trial, public opinion gradually changed from a large majority opposed to the charges to a small majority in favour of them, and a referendum resulted in the charges being reintroduced in 2007. This paper summarises effects on traffic, travel times, travel patterns etc., and discusses what lessons can be learnt from the trial and the development after the reintroduction of the charges.