Politicians’ support of or opposition to concrete policies is uniquely consequential for policymaking, public opinion, and a host of other societal outcomes. Explaining their policy positions is therefore a major research agenda in political science. Here, we evaluate the role of politicians' personality traits, measured with the Big Five typology, in shaping how liberal or conservative their economic and social policy positions are. While existing research establishes this link among non-elites, it is far from obvious that the same holds for politicians, who have systematically different personality profiles, and whose positions are constrained by party sorting. Using an in-person study of 895 incumbents in five countries who completed personality questionnaires and provided detailed issue positions, we find that Openness to Experience is a consistently strong and significant predictor of politicians' positions, but a null relationship for Conscientiousness. We discuss implications for the role of elites’ individual characteristics in policymaking.