“Acute Lung Injury (ALI) is a distinct form of acute respiratory failure characterized by diffuse pulmonary infiltrates, progressive hypoxemia, reduced lung compliance and normal hydrostatic pressures.” Trauma doctors involved in treating victims of war had long been familiar with this syndrome, which came to be known as “wet lung”, “shock lung” or “Da-nang lung”. This problem had been identified during World War II but with the advent of advanced trauma (M.A.S.H. units during the Vietnam war) the prevalence of this form of respiratory failure was truly recognized. Over the past 30 or so years, this syndrome has come to be one of the central problems of intensive care: lung injury arising from a variety of different etiologies, each characterized by bilateral diffuse infiltrates on x-ray, hypoxemia, and non-cardiogenic pulmonary edema.