Pilots of eHealth services often remain small or are discontinued due to various limitations in assessing their effectiveness and integrating them fully into care. A comprehensive evaluation tool called MAST assesses eHealth services across clinical, economic, user and organizational impacts to determine their potential for scale-up. Catalonia uses MAST to evaluate pilots, certify their interoperability, deploy necessary infrastructure to support scale-up, and conduct ongoing monitoring as services expand. This process helps decision-makers scale effective eHealth services that improve care in a sustainable way.