"The Presidentialization of Politics" shows how democratic political systems are coming to operate according to an essentially presidential logic, irrespective of their formal constitutional make-up. The logic of presidentialization is revealed in the growing power and autonomy of political leaders within political executives and political parties, and in the emergence of increasingly leadership-centred electoral processes. While these developments to some extent reflect the fluctuating contingencies of particular personalities and short-term political contexts, they are more fundamentally explained by processes of long-term structural change affecting state and society. Such processes include the internationalization of political decision-making, the executive's search for enhanced steering capacity over the state, the changing structure of mass communications, and the erosion of traditional political cleavages. The book presents evidence confirming the existence of the presidentialization phenomenon across a heterogeneous mix of established democracies. While there are significant cross-national differences, the overall thesis holds: Modern democracies increasingly follow a presidential logic which renders leaders both more central and more vulnerable, their power and their susceptibility each rooted in the capacity to sustain a personal appeal to mass publics.