BACKGROUND: The aim of this article was to study repeated suicidal behaviour in a low-incidence population to elucidate robust risk factors. METHODS: A cohort of first-ever suicide attempters from 1960 to 1982 on the Faroe Islands was followed up for a minimum of 20 years. The cohort was initially characterized in psychiatric and social terms. RESULTS: The incidence of suicidal behaviour for the cohort years (age 15 years and older) was 37.9 per 100,000 per year (95% confidence interval 31.5-45.1). It was associated, as expected, with gender, age, residence, marital status, occupation, diagnosis, previous psychiatric admission, alcohol intoxication and the method and planning of the act. Factors of the index episode predicting repetition at 5 years were gestures and alcohol intoxication and at 20 years were physical methods, suicide letter and alcohol intoxication. CONCLUSIONS: Alcohol intoxication and the level of determination behind the suicide attempt emerge as targets for prevention. Alcohol intoxication at the initial episode seems to be a strong long-term as well as short-term risk factor.