The tram is a sustainable mode of transport. However, tram tracks are often shared with vulnerable road users (VRUs) such as pedestrians and cyclists. In this mixed environment, accidents between trams and VRUs are very rare but severe at the same time. Previous studies have acknowledged that tram driving is a complex and very demanding task. Yet, subjective notions of traffic safety that are more connected with the behavior of tram drivers, have never been quantified. This is important in order to better interpret the challenges that tram drivers face. To do so, a stated preference experiment was designed in which tram drivers in Athens rated their perceived safety and driving stress of different driving scenarios on a 7-point Likert Scale. The driving scenarios were presented to the tram drivers using static images. According to the estimated perceived safety model, the alignment type (such as exclusive, semi-exclusive), the existence and the type of pedestrian crossing and the volume of VRUs influence tram drivers' perceived safety. Driving stress was affected mainly by arrival delay and load of standing passengers. Route familiarity also appeared as an important factor, that influences driving stress. No statistically significant correlation between perceived safety and driving stress was observed. One explanation for this is that experienced tram drivers believe that they are ready to respond properly in a section that they perceive as unsafe, if they are familiar with it. If there is no familiarity, tram drivers lack confidence and therefore driving stress is increased.@en