This session will present how a comprehensive Single Sign-On solution was designed and deployed at scale to provide a seamless user experience to millions of health professional across their web applications, desktop clients and workstations. Doctors are one of the most complex population in terms of usecases around Acccess Control: They can share workstations, either on a shift-based duration or for much smaller periods of time. They need access for a few minutes on a workstation and then another few minutes to the same software but on another workstation. They can't be bothered with typing in too much passwords. They might ask an assistant to impersonate them (and that assistant would impersonate several doctors). And they use A LOT of desktop clients. And they will continue to use them for a long time, web applications sometimes are just not the solution. Furthermore, some doctors have a physical national health professional smartcard, some only use a digital one on their smartphones and some use both depending on the situation. The session presents the history of the project, the recent and current developments as well as the foreseen updates for the short and middle term.