Recourse to mechanical ventilation may prove necessary in adult patients with cystic fibrosis who have reached the stage of severe respiratory insufficiency. We report the experience of an intensive care service using non-invasive ventilation (NIV) as the first step in the management of acute respiratory failure in these patients. The records of 16 patients with cystic fibrosis presenting with acute respiratory failure and treated with NIV were analysed retrospectively. The characteristics of the group were: mean age 26.9 +/- 9.5 years; mean FEV1 21.5 +/- 10.4% predicted; mean body mass index 16.8 +/- 2.1; mean Pa CO(2) on admission 66 +/- 15 mm Hg. The mean duration of NIV in the ICU was 10 +/- 7 days. Eight patients (50%) died after having been intubated on account of failure of NIV. The eight survivors were discharged home with long-term NIV (mean duration 235 +/- 158 days). Six of them have received a lung transplant. The mode of onset of respiratory failure was an important prognostic factor: a rapid onset (<7 days) was invariably associated with death, on the other hand a gradual deterioration (> 7 days) was noted in the eight patients able to leave the ICU. In conclusion NIV may be regarded as the treatment of choice in patients with cystic fibrosis admitted to ICU with respiratory failure. In the case of persistent hypercapnia after the acute episode long-term NIV may keep them stable while awaiting lung transplantation.