This document discusses chronic obstructive pulmonary disease (COPD). It defines COPD as a preventable and treatable disease characterized by persistent respiratory symptoms and airflow limitation. The main causes of COPD are tobacco smoking, exposure to indoor and outdoor air pollution, and occupational dusts and chemicals. Spirometry is used to diagnose COPD by demonstrating airflow limitation. The assessment of COPD involves evaluating symptoms, degree of airflow limitation, risk of exacerbations, and comorbidities. Treatment involves smoking cessation, pulmonary rehabilitation, pharmacotherapy including bronchodilators and corticosteroids, oxygen therapy, and vaccination.