This article examines how the crisis of intermediation has reshaped protest dynamics in contemporary Europe. Building on the argument that declining trust in intermediary organizations reflects a broader structural transformation, we focus on its implications for collective action. We argue that traditional actors, such as trade unions, political parties, and national-level social movement organizations, have lost centrality, giving way to more horizontal, locally rooted, and less mediated forms of mobilization. Empirically, we combine three data sources. First, we use the PolDem dataset for European countries (2000–2015) to identify cross-national trends in protest dynamics. Second, we analyze the DISDEM-ECOPOL dataset for Spain (2000–2020), a paradigmatic case of disintermediated mobilization, exemplified by the 15-M anti-austerity protests. Third, we draw on the European Social Survey to test the association between distrust toward intermediary organizations and disintermediated protests across countries over time. Our findings show a systematic decline in trust in traditional intermediaries, accompanied by a reduced presence of these actors in protest events and a rise of decentralized organizations. Less mediated protests are more likely to involve violent dynamics. At the same time, protest agendas increasingly emphasize territorial, environmental, and feminist issues. These results highlight the crisis of intermediation as a key driver of contemporary transformations in collective action.