Responding to Populist Parties in Europe: The ‚Other People‘ vs the ‚Populist People‘ provides a new theoretical tool kit exploring how those who disagree with populist parties oppose them and what kinds of opposition initiatives work, why, and to what ends. It argues that analogies with the interwar rise of fascism and postwar communist takeover to the East do not easily fit the reality of today’s Europe. Those opposing populist parties often swim in muddier waters than the past, necessarily navigating more complex questions about whether populist opponents deepen or threaten democracy. Populists also operate in a globalized, interdependent Europe, with overlapping spheres of territorial governance. This novel context, the book claims, not only helps us understand the rise of populist parties, but also the constraints of opposition. It begins with a new typology of tolerant and intolerant initiatives opposing populist parties, not just from public authorities and political parties operating at state and international levels, but also lesser-known initiatives from civil society. This forms the foundations of a ‚bottom up‘ approach for evaluating the effectiveness of opposition to populist parties, acknowledging substantial variation in opposition forms country-to-country and party-to-party. The book then outlines a goal-attainment theory of effective opposition, focusing on whether opponents manage to curb illiberal and anti-democratic policies, reduce support for populist parties, diminish their resources, or induce moderation, without producing perverse effects.