Self-poisoning accounts for a significant number of attendances to acute services. It can occur at any age. The reasons that lead someone to self-poison are variable and individual. It is often a manifestation of distress. Women are more likely to present, or die, after overdose than men, although men are more likely to die by suicide overall. Self-harm, including self-poisoning, is a strong risk factor and antecedent to suicide. Psychosocial assessment offers an important opportunity to intervene.