The results of an anatomohistopathologic study carried out on subjects who died from various causes in resuscitation centers are reported with specific reference to the evolutive phases of the adult respiratory distress syncrome (ARDS). While a precise anatomohistopathologic diagnosis of non-clinically diagnosed ARDS in its initial phase is considered possible, the importance of recognizing this pathology in cadavers and living patients is emphasized because of the medico-legal implications involved.