Does improving employee happiness affect customer outcomes? The current study attempts to answer this question by examining the impact of employee satisfaction trajectories (i.e., systematic changes in employee satisfaction) on customer outcomes. After accounting for employees’ initial satisfaction levels, the analyses demonstrate the importance of employee satisfaction trajectories for customer satisfaction and repatronage intentions, as well as identify customer-employee contact as a necessary conduit for their effect. From a macro perspective, employee satisfaction trajectories strongly impact customer satisfaction for companies with significant employee–customer interaction, but not for companies without such interaction. From a micro perspective, employee satisfaction trajectories influence customer repatronage intentions for frequent customers, but not for infrequent customers. These effects are robust to controlling for previous customer evaluations and recent employee evaluations. Overall, these findings extend the dominant view of examining static, employee satisfaction levels and offer important implications for the management of the organizational frontline.