In the TRANSPHORM study, noise exposures during commuting were measured. Measurements were performed with noise dosimeters in three European cities, Helsinki, Thessaloniki and Rotterdam, during spring 2011. ln each city, two to five approximately 8 km commuting routes were selected to represent typical commuting routes of the city population. Measurement campaigns lasted for 6 days, each day including 4 one-way drives on the same study route with a bike, a bus and a car with first open and then closed windows. In Helsinki, the median La"o levels were 72.9 dB, 7l .2 dB, 66.4 dB and 67.8 dB for a bicycle, a bus, a car with closed windows and a car with open co-driver window, respectively. Corresponding results in Thessaloniki were 74.9 d8,73.2 d8,70.7 dB and72.l dB. In Rotterdam, the median Li,"0 level during bicycling was 69.3 dB and during the bus journeys 68.9 dB. There were clear differences between the cities in the noise levels, but in all cities bicyclers were exposed to the highest noise levels, followed by the bus passengers. It is unclear to what extent noise effects on the selection between a private car and eco-friendlier commuting modes.