This project aims to systematically integrate two different representations of people’s dispositions to think and feel about justice and morality-related issues thus far reflected in two independent constructs: Justice Sensitivity (JS) differentiates between different perspectives that people take when reflecting upon issues of (in-)justice, whereas Moral Foundations (MF) differentiate between different content domains of morality. Both perspective-specific JS as well as content-specific MF are related to political ideologies and behavioral inclinations, such as voting behavior, but the question of whether a perspective-specific approach, a content-specific approach, or an integrative approach best predicts political attitudes has remained unexplored so far. This is surprising because an integrative approach seems particularly promising and can contribute to current debates in moral psychology, social justice research, and political psychology. Here, we pre-register a cross-sectional online study (N=2200) aimed at testing a measurement model based on items that combine four (JS) perspectives with five (MF) content domains ‒ the Moral Perspectives and Foundations Scale (MPFS). We predict that (1) this measurement model describes the dimensional structure of the 120-item MPFS better than either a four-factorial perspectives model or a five-factorial content domain model. We also predict that (2a) a self-oriented moral foundations sensitivity positively predicts right-wing political orientation, preferences for populist right-wing parties, and anti-immigration attitudes across all five moral foundations, and that (2b) an other-oriented moral foundations sensitivity positively predicts left-wing political orientation and negatively predicts preferences for populist right-wing parties and anti-immigration attitudes across all five moral foundations.