Organizations operate more effectively when managers trust their employees. In many cases, however, managers and their employees have divergent interests. One common managerial approach to address the problem of misaligned incentives involves monitoring employee behavior. In this paper, we investigate how monitoring changes the behavior of both those who are monitored and those who monitor others. Across three experiments, we paired participants in repeated trust games with different monitoring conditions. In each iteration of the repeated trust game, a trustor must decide how much money to pass to a trustee. The money passed is either tripled or quadrupled; the trustee must then decide how much money to return to the trustor. In each of three studies, we included conditions with anticipated monitoring. When trustees could anticipate monitoring, they engaged in opportunistic behavior; they returned more money than they received when they anticipated that they would be monitored, but either returned a small amount or nothing at all when they anticipated that they would not be monitored. Trustors, however, failed to appreciate how strategically their counterparts would act and continued to pass money to their counterparts even when they were unable to monitor them. Across three studies, we find that trustors systematically over-relied on the compliant behavior they observed during monitoring. We discuss managerial implications of these results for designing and using monitoring systems.2