Non invasive ventilation (NIV) is a system which delivers a preset pressure to supplement the size and depth of each breath. It is introduced in CF to manage established respiratory failure. A nose or a mask which covers both the nose and mouth allows flexible ventilation, is used just at night, or for part of the day in addition or for 24 hours as clinical status indicates. It is introduced within a normal ward environment and then continued longterm at home.Once respiratory failure is established longterm noninvasive ventilation is introduced throughout 24 hours and multidisciplinary assessment concludes that the timing is appropriate for the individual.