Josephina G Kuiper,1,2 Marina Bakker,1 Fernie JA Penning-van Beest,1 Ron MC Herings1,3 1Department Research, PHARMO Institute for Drug Outcomes Research, Utrecht, the Netherlands; 2Department of Public Health, Erasmus University Medical Centre, Rotterdam, the Netherlands; 3Amsterdam UMC, Vrije Universiteit Amsterdam, Epidemiology and Biostatistics, Amsterdam Public Health Research Institute, Amsterdam, the NetherlandsCorrespondence: Josephina G Kuiper Tel +31 30 7440 800Email josine.kuiper@pharmo.nlAbstract: The PHARMO Database Network provides a unique opportunity to gain insight in the complete patient journey and healthcare in the Netherlands. The PHARMO Database Network is a population-based network of electronic healthcare databases and combines anonymous data from different primary and secondary healthcare settings in the Netherlands. Healthcare settings include general practitioners, out-patient and in-patient pharmacies, hospitals and clinical laboratories. Furthermore, databases are linked with external registries such as the Cancer Registry, Pathology Registry and Perinatal Registry. The different data sources are linked on a patient level through probabilistic linkage based on validated algorithms. The longitudinal and ongoing nature of the PHARMO Database Network system enables to followup more than 10 million residents of the Netherlands for an average of 12 years. Data collection period, catchment area and overlap between data sources differ. Access to the PHARMO Database Network is, by governance regulations of the data collection, restricted to researchers of the PHARMO Institute and academic affiliates. Each data request is checked against privacy and company policies, and requires approval of the privacy and governance board. The terms and conditions and a data application form are available on the PHARMO website (www.pharmo.com).Keywords: database, record linkage, pharmacoepidemiology, observational research, electronic health record, Netherlands