RUIDO Photo has been doing projects of participatory photography in prisons of Catalunya since 2005, in a pioneer initiative in Spain. In these workshops coordinated by Pau Coll, the participants create their own photography and audiovisual projects with the supervision of a professional. In the last years, we have worked in the prison of Quatre Camins, in the Youth Prison of Catalonia and in a special unit of the adults prison Brians II. The result of this work has been shown in exhibitions, a short film and a documentary, with the goal of bringing to light this hidden reality to the rest of society.