Background: Suicidal behaviour has increasingly become recognized as a major public health problem. This study aimed to establish the extent of hospital-treated attempted suicide in South-west Ireland. Methods: Between 1995 and 1997, routine data collection, based on the standardized methodology of the WHO/Euro Multicentre Study on Suicidal Behaviour, took place in all general and psychiatric hospitals and prisons in the Southern and Mid-western Health Boards covering one-quarter (863,709) of the Irish population. Results: The annual person-based (aged over 15 years) male and female European age-standardized attempted suicide rates were 163 and 190 per 100,000, respectively. Female rates far exceeded male rates in under 20-year-olds. The peak rates for men and women were in the age range 20-24 (374 per 100,000) and 15-19 (433 per 100,000) years, respectively. One in six (16%) made a repeat attempt within the study period. Adjusting for age, repetition was marginally less common in women. Multivariate analysis investigating the risk of repetition associated with age, method and previous attempts found no age effect for women but an increased risk of repetition among men in their thirties (OR=1.7, 95% CI: 1.2-2.4). An attempt in the preceding 12 months greatly elevated the risk of repetition, particularly for women (female OR=13.7, 95% CI: 9.3-20.4; male OR=5.6, 95% CI: 4.1-7.8). Conclusion: Attempted suicide is a significant public health problem in Ireland. Rates are higher in women and highest among the young. An attempt in the past year greatly increases the risk of repetition, especially in women.