The growing interest in the populist phenomenon worldwide, which previously was centred on its protest and opposition functions, now includes its role in government. As a result in the recent years, research has shifted from the study of populism as an opposition, anti-system movement to the question of what populist governance and populist policies are. This article focuses on this topic, with a particular attention to welfare and socio economic policies of populists in power. It fills the gap in studies of policies of populism in power by assessing the state of the art of the research concerning welfare and socio economic policies and combining the theoretical perspectives of two distinct disciplines: political science and economic sociology. It unveils the features of populism in power (formal power, ideology, etc.); the dynamics of party competition, the relationship with social movements and the interactions among policy actors; the characteristics of the institutional context which can influence the (intensity and forms) of the intervention by populists in power on such policies.