In recent years, to protect the rights and welfare of human subjects, institutions in the USA have begun to set up programmes to monitor ongoing medical research. These programmes provide routine, onsite oversight, and thus go beyond existing oversight such as investigating suspected misconduct or reviewing paperwork provided by investigators. However, because of a lack of guidelines and evidence, institutions have had little guidance in setting up their programmes. To help institutions make the right choices, we used interviews and document (...) analysis to study how and why 11 US institutions have set up their monitoring programmes. Although these programmes varied considerably, we were able to distinguish two general types. ‘Compliance’ programmes on the one hand were part of the institutional review board office and set up to ensure compliance with regulations. Investigators’ participation was mandatory. Monitors focused on documentation. Investigators could be disciplined, and could be obliged to take corrective actions. ‘Quality-improvement’ programmes on the other hand were part of a separate office. Investigators requested to be monitored. Monitors focused more on actual research conduct. Investigators and other parties received feedback on how to improve the research process. Although both types of programmes have their drawbacks and advantages, we argue that if institutions want to set up monitoring programmes, quality improvement is the better choice: it can help foster an atmosphere of trust between investigators and the institutional review board, and can help raise the standards for the protection of human subjects. (shrink)