This paper describes the setup of the Dutch Mobile Mobility Panel project, in which GPS-enabled mobile phones (smartphones) are used as a passive multiple-week and multiple-year travel behaviour data collection tool. The data collection methodology used in the Dutch Mobile Mobility Panel comprised firstly the development of a smartphone application for iPhone and Android smartphones that automatically detects trips with its accompanying characteristics. Secondly, the trip data collected is enriched daily on a back-end server using data mining techniques to deduce suggestions for transport modes, places and trip purpose. In addition, additional data on weather conditions are added and errors in measurements are filtered out. Thirdly, an online follow up survey is conducted that enables participants to check and, if needed, revise trip characteristics or add or remove trips, and answer questions on specific travel conditions. Finally, participants fill in an online trip diary to report the trips for the first day of the field trial. This allows a comparison of the smartphone data collection with the conventional trip diary method. About 500 paid members of the LISS (Longitudinal Internet Studies for the Social sciences) panel are recruited to participate in the three-year mobility panel project, starting May-July 2013. The participants are a random sample of the Dutch population, and 20% smartphone owners (with iOS or Android operating systems) and 80% non-smartphone owners.