Cystic Fibrosis (CF) is a chronic, multi-system disorder that primarily affects the lungs, and pancreas, and leads to significant and progressive bronchiectasis, and subsequently end-stage lung disease. Sleep disturbances in cystic fibrosis include nocturnal hypoxemia due to a variety of physiologic changes including ventilation-perfusion mismatch, changes in mechanics of breathing. Derecruitment of ventilatory muscles, particularly during REM sleep and resultant hypoventilation may also be contributory, and may also lead to sleep-disordered breathing in these patients. Other potential causes of sleep disruption in CF patients include nocturnal wheezing and cough, as well as side effects of medications such as β-agonists, as well as chronic pain syndromes. It is likely that sleep fragmentation contributes significantly to impaired quality of life in CF patients. Nocturnal ventilation has been shown to improve symptoms, reverse hypoventilation and increase exercise capacity in CF patients.