The aim of this study was to ascertain prevalence rates of psychiatric disorders, suicidal ideation and intent, and parasuicide in a population of Irish adolescents aged 12-15 years in a defined geographical area. All 12-15-year olds attending eight secondary schools were eligible for inclusion. A two-stage procedure was used involving a screening and an interview phase. Those scoring in the clinical range on the screening measures were interviewed, along with a comparison group matched for gender, school and school year. 19.4% of the 723 screened were identified as being 'at risk'. This 'at risk' group was interviewed along with a comparison sample. 15.6% of the total study population met the criteria for a current psychiatric disorder, including 4.5% with an affective disorder, 3.7% with an anxiety disorder and 3.7% with ADHD. Significant past suicidal ideation was experienced by 1.9%, and 1.5% had a history of parasuicide. Binge drinking was associated with both affective and behaviour disorders. The authors conclude that rates of psychiatric disorders and suicidal behaviours are similar in young Irish adolescents to those in other Western cultures and that mental health promotion should be given priority in schools.