The incidence of acute lung injury (ALI) is influenced by nature of the underlying clinical condition. The frequency with which ALI is likely to be encountered by those practicing outside the intensive care unit (ICU) setting is largely unknown. Data from the paper under discussion indicates that ALI is seen relatively frequently in general wards and can be managed there until death or recovery. In patients with predisposing illnesses directly involving the lung, progression to ALI can be rapid.