Suicide by hanging and self-strangulation (‘hanging’) has become more common. We studied people who presented to hospital during a 28-year study period after using these methods for non-fatal self-harm. Hanging increased greatly in frequency during this time. The male:female ratio was nearly 3:1. Females were distinguished from males by far higher rates of psychiatric care, personality disorder and previous self-harm. Compared with matched individuals who presented with non-fatal self-poisoning, more of those who used hanging had high suicidal intent, fewer used alcohol in association with the act, and more subsequently died by suicide. They represent an important subgroup of those who self-harm, who require especially careful assessment and follow-up.