Abstract: Around the world governments characterized by observers as populist have taken power. Many of their actions have been incompatible with tenets of modern liberalism. This has generated commentary suggesting that populism is itself incompatible with constitutionalism. This Essay challenges that commentary. We agree that some variants of populism are incompatible with modern liberal constitutionalism but argue that the tension between populism as such and constitutionalism as such, though real, is significantly narrower than much commentary suggests. We begin in Section II by offering “barebones” definitions of populism and constitutionalism so that we can tease out precisely what the tension between them is. Section III turns to case studies of challenges to judicial independence, of the use of referendums, and of innovative methods of determining the public’s views. As with our discussion of defining populism and constitutionalism, here we attempt to identify whether (or the degree to which) the case studies demonstrate a tension between populism and constitutionalism. Our conclusion is that sometimes we can see such a tension and sometimes we cannot, and that the analysis of specific populisms and their policies in relation to constitutionalism must be highly sensitive to context. Section IV applies the argument to two developments in the United Kingdom: the Brexit referendum and the attempt by Boris Johnson to prorogue Parliament and the ensuing decision by the UK Supreme Court finding the prorogation unlawful. Here our conclusion once again that analysis of populism’s relation to constitutionalism must be sensitive to context: The referendum was flawed but not in ways that cast a bad light on populism as such, and the prorogation, while perhaps unlawful, was not clearly anti-constitutional. Overall we argue against generalized claims about populism as such and constitutionalism as such. There are many populisms and at least a few constitutionalisms, and scholars and observers should direct their attention to the questions posed by specific actions taken by individual populist governments. Sometimes populist governments will act in anti-constitutional ways, and sometimes they will not. We believe that this conclusion is appropriately deflationary.