The thesis explores a 5-year period in the political history of Spain. It looks at a series of political processes and projects, beginning with the 15M/Indignados social movement. These projects go from 15M in 2011 to the creation of new digital platforms for participatory democracy for the city of Barcelona in 2016. The thesis defends the idea that these cases add up to a cycle of political contention, which is defined as “the 15M cycle of contention”. It supports the idea that a core thread throughout the cycle has been the challenging of the liberal representative model of democracy and some of its key social forms, primarily in discourse, but also in practice. The cases within the cycle vindicated, and experimented with, alternative forms and practices of democracy. Concretely, they tried to move away from the current liberal representative model, preeminent since XVIII century, towards a more participatory one. The thesis also defends the argument that a key driver of these democratic experiments has been “technopolitics”, otherwise, practices and processes that hybridize politics and technologies (particularly, information and communication technologies). The thesis focuses on three paradigmatic cases of the 15M cycle of contention: 15M itself, a social movement born in 2011; the X party, a new party created in 2013 by 15M activists; and Decidim.barcelona, a digital platform for participation, launched in early 2016 by the Barcelona City Council, designed by people involved in previous projects within the 15M cycle. The first of these three cases covers the sphere of social movements and civil society, the second, that of political parties, and the third, that of the State at the municipal level. I look at the discourses and the practices of democracy in these processes and projects, and whether they innovate or not in relation to pre-existing political forms in social movements, political parties, and the State. In every case I look at the technopolitics deployed by the actors involved. For analyzing such technopolitics, I look at three main elements: discourses, practices, and technological infrastructures. These are used, respectively, as the main entry into the semantics, the pragmatics and the syntax of technopolitics. As a complementary view, I look beyond the cases and into the cycle. Concretely, to the variations in discourses on democracy and technopolitical practices. I suggest that the cycle as a whole can be conceived as: a) a process of “reassembling of democracy”, a reassembling oriented towards a democratization of the political field (and society more broadly) beyond the liberal representative model; and b) as a case of “technopolitical contention”, in which political struggles have been organically connected to technological practices. Since, differently from traditional democratization processes from XVIII century onwards, this one has not been oriented to establish but to challenge the structures of liberal representative democracy (f.i.: the current structure and centrality of representation, traditional political parties, Parliaments, etc.), I define it as an attempt at “alter-democratization”. I also show that this alter-democratization process challenges not only the forms, but also the ontology of liberal representative democracy, concretely, some of its key subjective and collective forms, as well as its key modes of political relation. By looking at civil society, parties and State institutions I try to map changes in various areas of the political field in liberal democracies. In that sense, the cycle has pointed towards (although has not always succeeded in bringing about) alternative political ontologies and forms of life. In order to analyze both the cycle and the three key cases under study, I have recurred to a multi-method and multi-disciplinary approach. I have primarily relied on qualitative methods, such as participant observation, fieldwork, interviews, and digital materials (blog posts, journals, etc.). I spent more than 5 years as participant in various 15M cycle projects. Secondarily, I have used quantitative methods: along with fellow activists and researchers, in 2014 we ran a digital survey that gathered 1000+ responses among 15M participants. Finally, I have also used social network analysis methods to map activity on social networks. In terms of disciplines, I primarily draw resources from political science, sociology, philosophy, and STS.