Chronic obstructive pulmonary disease (COPD) is a term that describes a disease state in which there is chronic irreversible airflow limitation. It has been well documented that patients with COPD have disturbed sleep. Certain published reports suggest that more than 50% of COPD patients have sleep complaints (George et al., Drugs, 2003). These patients are found to have sleep onset latency and poor sleep maintenance. While their sleep disturbance may be explained in part by side effects of medications, it could also be a result of nocturnal gas exchange abnormalities (Knutty 2004). In COPD there is worsening hypoxemia and hypercapnia during sleep, particularly REM sleep, and sleep disturbance seems to be worse with more severe COPD. It is commonly believed that optimizing medical management of the disease is important in improving the sleep quality of these patients and thus leading to improved quality of life.