Over time and across Western democracies, the media has become increasingly influential, and a great deal more political processes have become altered, shaped or structured by the media and the perceived need of individuals, organizations and social systems to communicate with or through the media. The key theoretical perspective to understand this process is mediatization. As a long-term process which has increased the importance of the media and their spill-over effects on political processes, institutions, organizations and actors, mediatization is one of the most important processes reshaping politics and transforming democracies across the Western world.