What is the effect of internal public management on individuals’ perceptions of managerial trustworthiness (MTW)? MTW is associated with a range of positive organizational outcomes, but research examining how a public manager might affect employees’ perception of MTW is sparse. This article complements extant research on MTW in public organizations with causal evidence from a randomized survey experiment among 1,829 U.S. residents. We examine how five aspects of internal public management affect individuals’ perception of MTW: (a) setting challenging but feasible goals, (b) making credible commitments, (c) encouraging employee participation, (d) providing frequent performance feedback, and (e) rewarding employees who perform well. We find positive effects of the "credible commitment" and "performance feedback" treatments on overall MTW perception. In addition, we find significant effects for four of the treatments (a-d) when looking separately at the three sub-dimensions that together comprise the multidimensional MTW construct (ability, benevolence, and integrity).