One decade ago, the World Health Organization recommended that water suppliers developed and implemented Water Safety Plans (WSP) as the most
effective mean to assure the quality of the water supply and the protection of the health of consumers. This model, as transposed in this guideline, consists of the overall risk assessment and risk management from catchment to tap, to protect the water to be destined to human consumption and the system, as well
as to control any process potentially affecting water quality, with the aim of assuring on a continuous way the absence of physical, biological and chemical hazards in drinking water. Risk based approach will also facilitate the flexibility of hazards management of emerging contaminants which are not systematically monitored, and /or vulnerabilities of water supply systems to direct and indirect impacts due to climate change. The guidance is addressed to water suppliers and health authorities as well as to all the stakeholders interested in different way to the drinking water quality. Criteria, methods and procedures are here provided in clear and practical terms to develop and implement WSP in drinking water supplies in Italy, independently by their dimension and by the volumes of supplied water.