Defence date: 6 December 2018Examining Board: Prof. Hanspeter Kriesi, European University Institute (Supervisor); Prof. Dorothee Bohle, European University Institute; Prof. Tim Haughton, University of Birmingham; Prof. Jan Rovny, Paris Institute of Political Studies.Post-2008 developments in European politics have reopened the debate on the extent to which we are witnessing a fundamental transformation of patterns of party competition and protest mobilization. Two phenomena in particular have drawn attention: the success of new parties and the rise of movement-like mobilization. Despite the attention devoted to them, it is unclear whether these developments have transformed the underlying programmatic structure and patterns of mobilization ...