Nasal ventilation is becoming increasingly recognised as an effective therapeutic strategy to minimise or correct hypercapnia in patients with respiratory failure. Intervention may be required on a short or long term basis. In the majority of patients, respiratory failure develops initially during sleep. Assessing patients at risk of nocturnal hypoventilation, and instituting appropriate therapy, is becoming an increasingly important aspect of respiratory care. This review outlines methods and practices involved in commencing nasal ventilation therapy. Twenty-nine patients presenting with hypercapnic respiratory failure were managed with nocturnal nasal ventilation over a 12 month period. With the use of this therapy PaCO2 fell from 64(2) to 50(1)mmHg (Mean(SE)) (p<0.001), while PaO2 improved from 55(2) to 68(2)mmHg (p<0.001) during a mean ventilation time of 10(0.8) days. Those factors which must be addressed for a successful program outcome are discussed.