Authors - Noah Holmdin, Martin Gilje Jaatun Abstract - The increased reliance on IT has resulted in a need for decision support for IT system usage scenarios. This is often done through risk assessment, where events are evaluated based on their likelihood of consequences and the severity of consequences. However, this may be difficult in scenarios when there is limited, uncertain, conflicting, or changing information about the IT system’s behaviour. A complementary approach for this is evaluating the system based on a Decision Maker’s (DM) trust in it. This paper introduces a subjective trust assessment framework for IT usage decisions.