This article presents the current state of knowledge in deliberate-self harm (DSH). DSH presents as a comorbidity with a number of personality disorders and psychopathologies, but is also relatively common in the psychologically healthy population. Over the past 10 years, attention has shifted from the investigation of DSH as a cardinal or comorbid symptom of psychopathology to an attempt to understand the behaviour itself, without reference to other psychopathological processes. It is argued that this development in understanding the aetiology of DSH has not been matched by developments in treatment or management of DSH, with the majority of treatment programs targeting larger syndromes of which DSH is a symptom. Treatment regimes aimed at reducing DSH appear to be either untested or demonstrably unsuccessful.