Smart cities in Switzerland are a part of the trend of digital transformation of public administration. These processes are led by local authorities in the municipalities (communes). Almost all aspects of public governance and public services can be considered as part of these digitisation efforts. Since Smart city programmes are designed by democratically led authorities, and because these programmes are goal-oriented and customer-centred in nature, we argue that local autonomy is necessary for a “good” implementation of a Smart city. However, the implementation of digital processes is mostly justified by gains of efficiency and effectiveness. Both technology as a tool, and the reasoning for implementing technologies might lead to centralisation processes and paradoxically, to a loss of local autonomy. The interests of cantonal and federal authorities to digitally transform public administration are already on the way to strip away the autonomy of municipalities in numerous areas. We argue that this tension, between local autonomy and a search for effective and efficient public services, is already present in the federal constitution and that the system lacks constitutional safeguards. Although further research is needed to better coin possible solutions, we suggest a few solutions that could help preserve local autonomy.