Grounded on a series of cases studies in Brazil, this thesis is an investigation of online audiences’ informal practices of viewing and distribution over the internet. As part of the steadily growing phenomena of peer to peer file sharing, television audiences across the globe are increasingly utilising the internet to informally access, distribute and/or facilitate access of television shows to others. For the purposes of this research, I use the term pirate audiences drawing from Ramon Lobato´s (2011) first use of the term, as well as similar uses such as “piracy audience” (Gustavo Cardoso, Lima, and Vieira, 2010), which are based on the notion of audiences involved in unauthorised practices of media sharing. I extend this conceptualisation of pirate audiences through an original empirical study. I examine how the concept of pirate audiences can offer a new way to understand piracy and audiences. I argue that this can be re-thought by exploring their informal practices of viewing and distribution of television content on the internet. Regardless of the source, generally, the content watched by a person who downloads is the same as a person who watches it on their television set. I draw from Nick Couldry’s (2011, 2012) work on everyday practices on digital media and analyse research on media file sharing and audiences’ digital practices. This analysis is developed through an investigation into how pirate audiences in Brazil create and maintain a parallel system of informal viewing and distribution of US television programmes through their informal practices on the internet. There is little research on television file sharing in Brazil as reports on internet use in the country only consider music, film and/or software downloading. Brazil is a BRIC country, one of the world’s largest economies and where over 20 million people are involved in unauthorised downloading of media. The investigation on Brazilian pirate audiences was undertaken using a mixed methods approach, which included qualitative and quantitative data collection. The main methods of data collection included online nonparticipant observation and analysis of downloading practices through websites and online communities in Orkut, online interviews and a focus group, and an online survey of 106 participants (n=106) who were regular downloaders of TV shows in Brazil. All data was coded and analysed by themes. The results demonstrate that informal practices are transnational because of the global reach of the internet. However, I argue that socio-political and economic aspects in Brazil have an influence on how people perceive and organise themselves in informal practices on the internet. This thesis supplements the literature on informal media economies and audiences research in online environments. By grounding the research in case studies in Brazil, the contribution to knowledge relies on making visible an activity that is considered criminal, but at the same time, it represents how audiences are evolving in the digital environment.