ALT Do Populists Listen to Expertise? A Five-Country Study of Authority, Arguments, and Expert Sources. Across diverse policy domains, there is broad concern about whether trust in science and expertise has eroded during the past decade. Using quota-based surveys with over 7,500 respondents across five countries and preregistered vignette experiments, we investigate what persuades populists and non-populists to accept expert advice. We find first that populism is associated with less willingness to accept expert advice, yet with variation between countries and topics. Second, we find both populists and non-populists are similarly impacted by stronger arguments. Finally, we show that populists are more likely to judge advice as poorly reasoned and perceive it as politically biased. A mediation analysis showed that the relationship between populism and advice acceptance was nearly completely mediated by these judgments. Our study indicates that populists not only listen to expertise but also