In the wake of the Great Recession many new parties have emerged throughout Europe. By adopting an anti-establishment narrative and oftentimes a populist posture, these parties have challenged the traditional or mainstream political actors which have characterized and structured West European party systems since the end of the Great Depression in the XX century. The present article explores the emergence of the «Great Recession Parties» and, in particular, it focuses on the main causal mechanisms explaining the recent electoral success of populist parties. More specifically, it evaluates whether and to what extent the populist surge is mainly driven by the economic downturn (the economic insecurity perspective), the reaction to the spread of progressive values in Western societies (the cultural backlash hypothesis) or the collusive behavior of mainstream political parties (the cartelization thesis). In the final sections, the article explores also the consequences of the emergence of populist actors for the dynamics and the stability of West European party systems.