Chronic obstructive pulmonary disease (COPD) shows a high mortality as well as a high prevalence around the world. Recent large-scale clinical studies showed that inhaled long-acting anticholinergics, inhaled long-acting β2-agonists, and inhaled corticosteroid have beneficial effects on patients suffered from COPD. In addition, the combination of the two or three inhalers above shows more beneficial effects. The beneficial effects are the improvement of symptom, lung function, and quality of life as well as the reduction of exacerbation and possibly death. These beneficial effects are true not only for the patients with severe and very severe COPD but also for the patients with moderate COPD. Clinical studies also showed that mucolytics and roflumilast, a new anti-inflammatory drug have beneficial effects on the patients with COPD. According to these beneficial results proven by the recent clinical studies, the guidelines for the management of COPD might be revised to promote the usage of the beneficial drugs for the patients with COPD. The promoted usage of the COPD drugs would help the COPD patients to overcome their symptom, limitation of airflow and frequent exacerbation and also to improve their quality of life. (Korean J Med 77:429-434, 2009)