The decision by the Stockholm City Council and the Swedish Riksdag to carry out a congestion tax trial in the inner city of Stockholm represented a major challenge to SL. The assignment that SL received from the Government in the summer of 2004 was to match in the best possible way the expected travel demand during the trial and to achieve this within a framework of an extremely short planning period of about one year. This resulted in the largest public transport investment since the underground was introduced in the fifties. The extended public transport started on August 22, 2005. Overnight, SL's entire traffi c output had then increased by seven percent. (The size of the new services corresponds to the size of public transport in Malmö). The project included extended fi xed track and bus traffi c, new depots and work-shops and additional lots for park-and-ride facilities at locations suitable for SL's travellers. To study the effects of the Stockholm Trial, an extensive evaluation program has been carried out. This report shows and summarizes the effects of the Stockholm Trial from a public transport perspective - the effects on SL's traffi c, the demand for travelling by SL, and the degree of satisfaction and quality as experienced by travellers. The report further includes a description of the planning phase and the problems that always arise when the field is "unploughed", time-frames are short and resources limited. We hope that the description may serve a wider purpose in future research and studies.