At the Martini Hospital Groningen, Yes Human Factors developed with the Martini “OR-Core team", a program for approx. 200 OR-employees in whichimproving patient safety is the key issue/goal. In spring 2018 the introduction program started in which Shared Situation Awareness is explained. After that the "0/zero" measurement starts in the cockpit simulator in which participants are observed on their own actions, the cooperation in the team and the the environment- and situation awareness.