Introduction: Political agenda-setting and mediatization as distinct worldsAgenda-setting is one of the most influential theories on the media's political influence (Graber, 2005). While often focusing on the media's impact on public opinion, another equally important facet of agenda-setting theory has the media's influence over the agendas of political actors and policy makers as its central object of investigation. Scholars use the term 'political agenda-setting' and in some instances 'agenda building' to refer to the transfer of media priorities to political priorities. Despite the growing popularity and importance of political agenda-setting research, it has seldom been conceptualized as part of or related to the mediatization of politics.For several reasons, political agenda-setting studies and mediatization studies have developed as almost completely distinct research schools (but see Van Noije, Oegema, & Kleinnijenhuis, 2008). Political agenda-setting studies share a strong empirical focus. They deal mainly with testing the effect of the media agenda on the political agenda in different contexts and circumstances. The basic question underlying most of the research reads: does more journalistic attention for an issue lead subsequently to more attention for that issue by politicians? With the help of sophisticated methods such as time series analyses researchers have been able to provide a nuanced and detailed answer to this question, identifying a set of contingent factors that determine the size and strength of the effect. While being empirically strong and analytically sophisticated, political agenda-setting work has, until recently, remained somewhat undertheorized. In particular, insights on why and how politicians adapt 2 to the agenda of the media are still in need of elaboration. Furthermore, agenda-setting focuses only on thematic priorities and it remains unclear how the impact of the media on issue agendas relates to other types of influence.The literature on mediatization, on the other hand, has been characterized by a broader theoretical input and goals (see chapter 1 and Y?), as well as by a broader scope covering media influence on several areas outside politics. The thesis on mediatization of politics provides an overarching view on the role of the media in the political system, and is in this volume defined as a long-term process through which the importance and influence of media in political processes and over political institutions and actors has increased (see chapter 1).While being strong on conceptual discussions and theoretical perspectives, the mediatization literature is lacking in empirical research.. Admittedly, some recent studies explore mediatization empirically. For instance, related to the 3 rd dimension of mediatization (see chapter x), Strömbäck and Nord (2006) find that journalists retain the most power over the content and framing of news while other studies document how mediatization of news content is stronger in the US compared to Europe (Strömbäck & Dimitrova, 2011;...