This paper aims to analyze and provide parameters for radio ombudsman services, considering the ombudsman experience carried out by the Brazilian Public Communications Enterprise (EBC) radio stations. The analysis of the listeners’ feedback during July 2008–September 2011 allows us to conclude that the ombudsman experience may be considered a Media Accountability Instrument (MAI) focused not only on journalism but also on music and entertainment. The ombudsman performance may be a MAI because it provides visibility and transparency to errors, issues and dilemmas associated with the media actions. Thus it stimulates more credibility, prompt discussion with readers, listeners and viewers, and could encourage a culture of greater accountability in the newsroom. The EBC ombudsman sought to be a mediation channel that provides visibility to matters raised during the weekly radio program: Radio in Debate.