This volume of the Netherlands Yearbook of International Law explores the many faces of populism, and the different manifestations of the relationship between populism and international law. Rather than taking the so-called populist backlash against globalisation, international law and governance at face value, this volume aims to dig deeper and wonders ‘What backlash are we talking about, really?’. While populism is contextual and contingent on the society in which it arises and its relationship with international law and institutions thus has differed likewise, this volume assists in our examination of what we find so dangerous about populism and problematic in its relationship with international law.