This entry describes trust as a key concept of modern societies and therefore of strategic communication. Generally speaking, trust reduces social complexity, thus providing the subjects of trust with the capability to act despite a lack of information. Trust is considered a crucial precondition for constant, loyal relations between organizations and their stakeholders. Trust is generated in the course of communicative processes while at the same time also being a precondition for successful communication between individuals or individuals and organizations. Whether trust develops or not, and to what extent, can be considerably influenced by the way in which the object of trust presents himself or herself. Thus, strategic communication is of crucial significance for the establishment of trust. This entry discusses essential concepts of trust in sociology, business economics, and psychology, and delimits trust from concepts such as distrust and familiarity. It also looks at three types of trust relations relevant to strategic communication.