This conclusion presents some closing thoughts on the key concepts discussed in the preceding chapters of this book. The book describes the growing involvement of mass communication and media in a variety of political arenas, and the pursuit of what we might call performance politics at all stages in the process by which issues emerge in the public sphere to be debated, negotiated around and, on occasion, resolved. It examines the use of public relations, marketing and advertising techniques by political parties, in campaigning and governmental mode. The chapter considers the role of journalists and their media as political reporters, interpreters, commentators and agenda-setters, observing how their relationship of interdependence with politicians has shaped the behaviours and professional practices of both groups. It also considers the emergence of online media channels, of citizen journalists and content-generating users of Twitter, YouTube and Facebook.