The prevalence of attempted or completed suicides was studied in the families of a consecutive sample of suicide victims, aged 15-29 years. In 40% of the men & 31% of the women, suicidal behavior was found in first-degree relatives. Males with a family history of suicidal behavior had an earlier debut of their own suicidal behaviour. Taking into account suicide by a friend or second-degree family member, it was found that 72% of victims had a history of suicidal behavior in close relationships.