The authors investigate the impact of direct democracy on aspects of the political process in Switzerland. They dwell in particular on the concrete use of the instruments of direct democracy by organized groups of citizens, and on the effects of this use on collective protest movements (or social movements) at the local level. The essay divides into three parts. The first briefly describes the institutions of direct democracy. The second deals with the concrete use of the instruments of direct democracy. The third examines the effects of direct democracy on the political process and on social movements. The authors highlight the paradox of direct democracy, at both the local and national level, between consensus and polarization with respect to the action of social movements.