In the last decades there has been a visible increase in self-harming behaviour. Although this fact could have been influenced by the increased interest of specialists in researching this phenomenon and the related development and specification of adequate diagnostic tools, it is certain that this specific behaviour, until recently considered highly pathological, is becoming a norm to such an extent that a significant number of individuals try it at least once in their life or even practice it for an extended period of time. Despite the preliminary establishing of self-harm as an isolated symptom in the diagnostic manual DSM-VTM, we cannot find its unified and generally acknowledged definition in relevant specialised literature because it is a complex phenomenon and its exact description entails a number of disunities in terms of terminology resulting from the various ways of understanding it.