With an aging global population, chronic respiratory diseases are becoming a more prominent cause of death and disability. Age-standardised death rates from chronic obstructive pulmonary disease (COPD) are highest in low-income regions of the world, particularly South Asia and sub-Saharan Africa, although airflow obstruction is relatively uncommon in these areas. Airflow obstruction is, by contrast, more common in regions with a high prevalence of cigarette smoking. COPD mortality is much more closely related to the prevalence of a low forced vital capacity which is, in turn, associated with poverty. Mortality from asthma is less common than mortality from COPD, but it is also relatively more common in poorer areas, particularly Oceania, South and South-East Asia, the Middle East and Africa. Again this contrasts with the asthma prevalence among adults, which is highest in high-income regions. In high-income areas, mortality due to asthma, which is predominantly an adult problem, has fallen substantially in recent decades with the spread of new guidelines for treatment that emphasise the use of inhaled steroids to control the disease. Although mortality rates have been falling, the prevalence of atopy has been increasing between generations in Western Europe. Changes in the prevalence of wheeze among adults has been more varied and may have been influenced by the reduction in smoking and the increase in the use of inhaled steroids.