Despite substantial progress in reducing the global impact of many non-communicable diseases, including heart disease and cancer, morbidity and mortality due to chronic respiratory disease continues to increase. Many factors have contributed to what must now be considered a public health emergency: failure to limit the sale and consumption of tobacco products, unchecked exposure to environmental pollutants across the life course, and the ageing of the global population (partly as a result of improved outcomes for other conditions). In particular, we advocate for: broader understanding of risk factors (including the devastating effects of global poverty) and the preventive measures necessary to avoid future cases of COPD, disruptive approaches to diagnosis that are not solely based on spirometric airflow limitation but also involve identification of early pathological changes that are more amenable to reversal, classification of the disease into types that share pathophysiological similarities and could lead to novel preventive and therapeutic approaches, and a new approach to the diagnosis and assessment of exacerbations of COPD that focuses on disease mechanisms. An acute worsening of COPD is termed an exacerbation, and such episodes account for a substantial proportion of the attributable cost of the disease and are associated with accelerated lung function loss, prolonged impairments in quality of life, and similar prognosis to many stage III or IV solid organ malignancies.