ABSTRACT This article builds on the insights of Antonio Gramsci and Stuart Hall to introduce the ‘critical-relational’ approach to the analysis of left-wing ideologies that have been defined as populist. In doing so, we identify four distinctive ideologies: ‘populist social democracy’, ‘populist socialism’, ‘popular social democracy’ and ‘popular socialism’. Two key contributions are made. First, the ‘relational’ aspect of this conceptualization establishes clear distinctions between ideologies that appeal to the ‘people’ either to: (i) democratically empower (‘popular’) or disempower (‘populist’) disenfranchised groups; and/or (ii) disrupt economic class relations (‘socialist’) or redistribute them without transforming them (‘social democratic’). These distinctions, we contend, shed light on important differences between left-wing ideologies that are often conflated in the literature on left populism. Second, the ‘critical’ aspect of our interpretation aims to reveal how discourses of the ‘people’ are mobilized within left-wing ideologies to either reproduce or contest economic and political structures of power. Overall, this provides grounding for a more precise empirical analysis of the diverse ideologies that characterize the political left.