Corruption is a worldwide concern. Within Tanzania, the landmark Warioba report (URT, 1996) confirmed the existence of extensive corruption across all sectors of the country, including in the public health sector where corruption has been reported at almost every stage of care-seeking. Based on an in-depth review of peer reviewed and grey literature, and complemented by key informant discussions with selected health-system stakeholders, this study seeks to deepen our understanding of informal practices amongst frontline public health providers in mainland Tanzania’s health sector, to explore the incentives that give rise to such practices, and to identify current formal and informal accountability and system-strengthening measures. Taken together, this evidence can be used to inform policy and practice in order to constrain such informal practices.