Modern healthcare systems are evolving towards a complex network of interconnected services. The increasing costs and the conversely increased expectations for high service levels leveraged the birth of healthcare monitoring activities and the proposition of numerous performance evaluation indicators. Generally, the adopted performance measures allow to draw a picture of quality, equity, appropriateness and efficiency of the medical care at different levels: caregiver, hospital, local health authority, region. The role of network organization and its impact on the performances is largely underestimated. It is difficult to build a Value Stream Mapping of the healthcare network because of the number and complexity of care and diseases followed. The study tries to overcome this issue. Starting from a database of the accesses to the services in a local health agency, the activity flow diagram is produced by using a process mining software, Disco. A knowledge structured by means of an ontology allows to describe the logic behind the health service provision. The resulting process flow chart is the base for the identification and amendment of redundant and non value added flows among services.