Drawing on debates on deliberative and participatory democracy, I argue that social movements can be considered to be promoting democratization when they are able to compel governments to increase effective participation in the policy-making process, and/or when their democratic claims are translated into an agenda and/or policy impact. This indicates that a social movement has increased the responsiveness of the government it is challenging. Based on this premise, in this paper, I trace the political impact of the Student Movement in Chile. Spearheading the largest protests since the reinstatement of democracy, in 2006, and most notably, in 2011, the Student Movement forced a debate on education and political reforms, and a series of policies to address these issues. The analysis is grounded on more than 50 interviews, and an exhaustive analysis of organizational documents and newspaper data. The case examined in this paper illustrates how the expansion of political opportunities that is necessary for pursuing democratizing reforms not only is driven “from above,” but also “from below.” Studying this process, social movement scholarship can learn a great deal from recent cases of social mobilization in Latin America. These experiences also call for more attention to the role of social movements in democratization studies.