The optimal therapy of an individual with chronic respiratory disease usually requires a combination of pharmacologic and non-pharmacologic therapies. A case of a 68-year-old man with advanced chronic obstructive pulmonary disease is given to illustrate this point. He is a recent ex-smoker with severe chronic obstructive pulmonary disease by spirometric criteria, frequent exacerbations of this disease, considerable recent health care utilization, dyspnea with minimal activities, severe functional status limitation, prominent systemic effects of the disease (e.g., weight loss) and substantial comorbidities. The primary respiratory disease cannot be isolated from and treated independently of these important factors. Pulmonary rehabilitation is an important therapeutic option in situations like this, providing a mode of integrating care, complementing otherwise standard medical therapy, and producing significant gains across multiple outcome areas of importance to the patient. Pulmonary rehabilitation has been defined by the American Thoracic Society and European Respiratory Society as: "an evidence-based, multidisciplinary, and comprehensive intervention for patients with chronic respiratory diseases who are symptomatic and often have decreased daily life activities. Integrated into the individualized treatment of the patient, pulmonary rehabilitation is designed to reduce symptoms, optimize functional status, increase participation, and reduce health care costs through stabilizing or reversing systemic manifestations of the disease". Its components include comprehensive assessment, education, exercise training, and psychosocial intervention. Outcomes assessment is usually performed for quality assessment. Pulmonary rehabilitation produces the greatest improvements of any available therapy in dyspnea, exercise capacity, and health-related quality of life. These gains are realized despite the fact that pulmonary rehabilitation has no direct effect on lung function. It works primarily through reducing the impact of the systemic manifestations of the disease and frequent comorbidity. Pulmonary rehabilitation also leads to substantial reductions in subsequent health care utilization, possibly through collaborative self-management strategies emphasized in the program. Although pulmonary rehabilitation has been utilized by astute clinicians for many years, its science has been developed over the past two decades.