Chronic obstructive pulmonary disease (COPD) is a preventable and treatable disease in which patients experience a progressive decline in lung function, worsening exercise capacity, and frequent exacerbations. Based on clinical evidence, the progression of COPD could be modified by focus on earlier diagnosis; risk reduction through smoking cessation; symptom reduction with pharmacotherapy, improving health-related quality of life, and pulmonary rehabilitation; and decreasing complications by reducing exacerbations. Smoking cessation has been shown to slow lung function decline and reduce mortality, including deaths due to cardiovascular disease, lung cancer, and other respiratory disease (including COPD).