Surveillance of HAI is critical to inform and guide IPC strategies. • Health care facility surveillance should be based on national recommendations and standard definitions and customized to the facility according to available resources with clear objectives and strategies. Surveillance should provide information for: › describing the status of infections associated with health care (that is, incidence and/or prevalence, type, aetiology and, ideally, data on severity and the attributable burden of disease); › identification of the most relevant AMR patterns; › identification of high risk populations, procedures and exposures; › existence and functioning of WASH infrastructures, such as a water supply, toilets and health care waste disposal; › early detection of clusters and outbreaks (that is, early warning system); › evaluation of the impact of interventions. • Quality microbiology and laboratory capacity is essential to enable reliable HAI surveillance. • The responsibility for planning and conducting surveillance and analysing, interpreting and disseminating the collected data remains usually with the IPC committee and the IPC team. • Methods for detecting infections should be active. Different surveillance strategies could include the use of prevalence or incidence studies. • Hospital-based infection surveillance systems should be linked to integrated public health infection surveillance systems. • Surveillance reports should be disseminated in a timely manner to those at the managerial or administration level (decision-makers) and the unit/ward level (frontline health care workers). • A system for surveillance data quality assessment is of the utmost importance.