Encouraging citizens to apply pressure on underperforming service providers has emerged in recent years as a prominent response to the failure of states to provide needed services. We outline three theoretical mechanisms through which bottom-up citizen-oriented pressure campaigns may affect development outcomes and investigate them via a large-scale field experiment in the Ugandan health sector. While we find modest positive impacts on treatment quality and patient satisfaction, we find no effects on utilization rates, child mortality, or other health outcomes. We also find no evidence that citizens increased their monitoring or sanctioning of health workers. Our findings, therefore, cast doubt on the power of outside actors to generate bottom-up pressure by citizens or improvements in development outcomes. Held up against the findings of other, similar studies, our results point to the salience of mechanisms other than citizen pressure for improvements in service delivery, and to the importance of baseline health conditions for the success of bottom-up, citizen-oriented pressure campaigns. Such conditions shape outcomes both across countries and within countries over time, with the latter finding holding important implications for countries undergoing rapid socioeconomic change.