The diagnosis, pathophysiology, and treatment of adult respiratory distress syndrome (ARDS) are discussed and 2 cases are presented. ARDS has varied etiology but common clinical, roentgenographic, and pathologic findings; it has been increasingly recognized as an important cause of morbidity and mortality in seriously ill patients. The obstetrician-gynecologist must be aware of this condition, for survival depends upon prompt diagnosis and meticulous therapy of the condition and its underlying cause.