Recent years have been fertile in new forms of collective mobilization and activism. In this context the digital media have been assuming a particularly important role. This article is based on an exploratory project, carried out between 2014 and 2015, which sought to study the use of digital media with the forms of activism and public participation of young people in Portugal. Methodologically this project took a qualitative approach, which sought to articulate a research online and off-line. The conclusions presented derive from an analysis of in-depth interviews carried out with activists belonging to different collective actors.