Since the first report by Ashbaugh and Petty in 1967 categorizing patients with acute respiratory failure and labelling the process the adult respiratory distress syndrome (ARDS), this illness has been recognized with increasing frequency. Adult respiratory distress syndrome now afflicts more than 150,000 people a year and the mortality remains in the 70 percent range in spite of significant advances in critical care medicine. As a consequence, research in the area of acute lung injury has intensified resulting in the elucidation of many of the pathophysiologic mechanisms operative in the process. As long as the mortality of ARDS remains high, research of this kind will be needed especially with regard to clinical trials of pharmacologic agents which have appeared promising in the laboratory. An aggressive approach, possibly utilizing multiple drug regimens, seems justified considering the morbidity and mortality with which are dealing. Until success is achieved, supportive intensive care with diligent attention to oxygen and ventilator management, infection control, and fluid therapy will be the mainstay of treatment for ARDS.