Expressive Writing as a Coping-Tool. A State of the Art Review This article provides a state of the art review on the research on Expressive Writing (EW). In the paradigm originally developed by Pennebaker, participants write about a traumatic experience or a neutral topic on 3–4 days for 15–20 minutes. A large number of studies has now documented the positive effects of EW on physical and mental health. It has been shown that in the months after the study, participants who write about a traumatic experience go to the doctor less often, show improved immune function, report fewer symptoms, are less depressed and anxious and have generally a higher well-being as compared to the control group. Three major models have been proposed to explain the effects of EW. The initial studies assumed that a disclosure induced physiological disinhibition was responsible for its effects. Current research focuses on linguistic and cognitive processes according to which EW fosters the development of a coherent narrative about the events that then can be stored more efficiently and be forgotten more easily. According to the most recent model, EW facilitates social processes that enable individuals to approach others more actively and become better integrated into their social network. Other approaches focus on habituation processes as potential mediators. The different models can be integrated in an emotion regulation model. Finally, potentials of the paradigm in the real world are discussed and show how EW can be used for personal, educational and therapeutic purposes.