Misophonia is a new and relatively under-explored condition characterized by experiencing strong emotions (mainly anger and disgust) and a physical response (such as muscle constriction, increased heart rate) when exposed to specific sounds. Among the most frequent aversive triggers are the sounds of eating, breathing, or typing. The experience of misophonia is associated with suffering and a significant decrease in quality of life. The phenomenon was first described in 2002. Since then, numerous case studies and data from psychophysiological and neurological and survey research on this phenomenon have been published. These data indicate that misophonia is a consistent phenomenon and preliminary identification is possible. The most recent results show that misophonia occurs independent of other disorders. There are still, however, many questions regarding the definition and diagnostic criteria to be answered. The most important diagnostic issues that are faced during clinical work with people with misophonia are described in this article. Furthermore, the main theoretical concepts and research on misophonia are reviewed and analyzed.