In many Western countries, the car is still the dominant travel mode for everyday travel. In the US there has been a dramatic increase (194 per cent) in vehicle trips and vehicle miles of travel from 1969 to 2001 (NHTS, 2001a). In the year 2001, 86 per cent of the number of trips and 88 per cent of the travelled miles were made by private vehicle (NHTS, 2001b). In Europe today, on average 70 per cent of the travel distance is made by car (Eurostat, 2007). The car is used for trips to work, to the store, to leisure activities, and to give others, such as children, a lift to different locations. Hence, the car is an integrated part of many peoples’ lives. However, traffic causes both local and large-scale environmental problems, such as noise, landscape fragmentation and different types of emissions (e.g. carbon dioxide CO2) (Trocmé et al, 2003; Miedema, 2007; Van Wee, 2007). Given that personal transportation is a significant contributor to environmental problems, the negative environmental effects of car use need to be reduced. Different policy measures may be implemented in order to encourage more sustainable travel behaviour. Three broad strategies are land management strategies, such as planning for more compact cities (Litman, 2008), technological improvements, such as developing cars fuelled by renewable fuel, and reducing the demand for car use through, for example increasing the cost for using cars and decreasing the cost for using alternative travel modes (Gärling et al, 2002). Although all three strategies are needed in order to achieve more sustainable travel behaviour, several researchers advocate that an immediate reduction in the negative environmental effects of transportation demands a change in travel behaviour (see e.g. Hickman and Banister, 2007).