Who intervenes in the discussion of issues that affect the common interest? Who has the ability to be visible or not in the media scenarios according to their own interest? Who are the object of exposition and who are the subjects of enunciation? This book analyzes these questions from the changes in the media scene and contributes theoretically and methodologically to the investigation of communication from the conceptual and operational construction of objects, contextual reflection, the elaboration of analysis matrices and the articulation of various study perspectives.