ABSTRACT Over the last 30 years, scholarship has produced countless books, essays, and articles on populism by investigating it from various perspectives and angles. This article seeks to contribute to this ongoing debate by offering a political-philosophical reconstruction of populism to define such a phenomenon from a multilateral perspective. The essay will proceed as follows: The first section will investigate populism from a purely political-philosophical position, while the second will discuss the constitutional effects of such a phenomenon, to define it mainly as a form of anti-liberal and anti-judicial redefinition of democracy. Moreover, the first section will expose the dichotomy between the so-called left- and right-forms of the populist model and the populist threat to democracy, where the second will address populist constitutionalism and its antithetic relation to liberal constitutionalism. 1 1 This article is the result of a period of research spent at the CAS-SEE UNIRI – Center for Advanced Studies of the University of Rijeka, Croatia. I wish to thank the Institute and its members for the opportunity to develop this research. Part of this research has been presented at the doctoral seminar of the Doctoral School of History and Philosophical-Social Sciences, University of Rome Tor Vergata. I wish to thank my colleagues Alessandro Ferrara, Matteo Bianchin, Tonino Griffero, Claudia Gina Hassan as well as the doctoral students of our programme, for comments and suggestions.