The paper discusses the theoretical concepts, design considerations and preliminary findings from Smart Mobility, a research project currently being undertaken with the City of St. Gallen. The project aims at designing measures to encourage the increased use of public and non-motorised transport by integrating behavioural economic principles into public policy. The extensive involvement of citizens and their participation in the design of the measures are to support their democratic legitimization and later acceptance. The paper describes the energy policies behind the project and outlines the theoretical framework for integrating behavioural insights into public policy. The strategies envisaged include participatory instruments and methods, especially the use of existing social media channels, capitalizing on social processes and norms to increase the motivation of individuals to use public transport, creating an open innovation space by means of crowdsourcing as well as the proper framing of political communication to achieve changes in mobility patterns.