ABSTRACT
The chapter contains a presentation and discussion of distinct subgroups of people with NSSI in non-clinical populations. These studies document the diverse make-up of the population of people who engage in NSSI. One argument in favour of making NSSI an autonomous clinical diagnosis would be it has clinical unity, in the sense that it represents a specific behaviour and not just a diagnostic criterion of Borderline Personality Disorder. Finally, differential diagnoses are discussed: suicide attempts, Borderline Personality Disorder, Factitious Disorder and Sadomasochism.
