The Brazilian Landless Workers’ Movement (MST) has since its creation in 1984 acted for the promotion of agrarian reform and rural workers’ and their families’ rights to education, healthcare, culture and infrastructure. Throughout its trajectory, the social movement faced the difficulties that arise from the scarcity of arenas and resources to communicate. Recognising at early stage that voice matters (cf. Couldry 2010) and that the means to form and express opinions are not equally available in a society, MST has since its foundation being active in constructing and maintaining communication channels on the side of the core cause of promoting agrarian reform. The article is based on fieldwork carried out in 2013 and 2014 and interviews with MST militants working with communication. The analysis of the material raises questions of relevance, potential and actual achievements of media activism. From the realisation, at an early stage, that voice is an important element in the promotion of social change; MST started their activities as incidental media activists. These activities run parallel and complement the movement’s work and include demands to change community radio legislation in Brazil and participation in FNDC, the National Forum for Democratisation of Communication. Based Fraser’s (2009) view of justice as a matter of recognition, redistribution and representation and on Couldry’s (2010 and 2013) critique of corporative media’s role in neoliberalism, this article discusses the experience of MST in becoming an incidental actor in the democratisation of media. The term incidental is used here to draw attention to the importance of voice for those considered marginal, even if acting on another aspect of marginality.