Trust is not only one key ingredient of prosperous organizations and societies, but also an essential factor in decision-making processes. And when it comes to trust, the latest advances in computing sciences area are increasingly supporting the related processes by deployment of so-called trust management systems. These systems are slowly advancing from their early stages of evolution toward more sophisticated and already operationally deployable solutions. As there seems to be no \Swiss-army knife" like methodology for trust management, it is reasonable to assume that not only one, but a few of them will be deployed in the future, depending on their basic principles of functioning,purposes and contexts of use. Therefore there still exists a gap in this area with unaddressed issues where humans (or humans-like agents) would be in focus. Quality Assessment Dynamics, QAD, which is presented in this paper, is taking these issues into account. It is based on operands and operators that model human ways of reasoning as described in many natural languages. Further, it is a formal system and therefore enabled for deployment in computing environments. This way QAD complements existing trust management methods and provides additional means for decision making through deployment in simulations and in trust management engines, while being understandable to ordinary users without requiring sophisticated expert knowledge.