What Are populists good for democracy? Or, do they undermine it? How should we react? Should we even react at all? Many European democracies now face these questions. The project aims to address the question of how European democracies respond to populists in practice and what works. Responses to populist parties include policies and acts of public authorities, political party strategies and civil society mobilisation. They can be deployed locally, at state level and at the international and EU level. It includes ostracism, judicial review, and direct action by national and transnational NGOs. The project will produce a book with theoretical reflections on how to identify effective responses to populist parties and illustrative examples to guide research and public policy. Why The Brexit referendum, growing support for populist programmes, and more populist parties in government, makes the question of responding to populists pressing. We know a great deal about why populists breakthrough electorally and who supports them. There is a lively debate about whether populism is a ‘pathology’ or a ‘corrective’ for liberal democracy. We know much less about the focus of this project - how to respond to populists. Features of the contemporary ‘populist playbook’ also complicate the issue of responses: Populists positions on democracy tend to be more ambiguous than extremists, making choices of responses more complex. Populists have become 'global actors', producing responses encompassing multiple territorial levels. How The book will argue that old-style repressive measures of militant democracy won’t work against populists. Political grievances need to be aired. Yet populists’ ability to implement anti-democratic and anti-liberal measures should be constrained by the multilevel system of institutional checks and balances in Europe; robust procedures against corruption and misrule; transnational and domestic civil society resistance; and mobilisation of the profound interdependence of European states to promote compliance with existing commitments to liberal democratic governance. The book includes a new typology of responses to populist in Europe; identifies the main goals of the responses and 'perverse' effects, and presents a new model of 'democratic defence' for European multilevel governance. SSR The repressive nature of many responses to populist parties raises a democratic dilemma: On the one hand, many populist parties win a substantial share of votes in mostly free and fair elections. On the other hand, many initiatives opposing populism aim to limit the influence of populist parties in the public sphere. The project contributes to long term aspects of Social Scientific Responsibility by exploring the variety of ways in which different democratic communities in Europe respond to this dilemma in practice.