This paper provides evidence that the personalities of policymakers matter for policy. Three results support the relevance of personalities for policy. First, doctors with higher Big Five and Perry Public Sector Motivation scores attend work more and falsify inspection reports less. Second, health inspectors who score higher on these measures exhibit larger treatment responses to increased monitoring. Last, senior health officials with higher personality scores respond more to data on staff absence by compelling better subsequent attendance. These results suggest that interpersonal differences matter are consequential for state performance.