This article on toxemia of pregnancy is based on the study of this condition at the Sloane Hospital for Women during the past fifteen years. Nine hundred and thirty cases have been observed, 594 of which have been followed up in at least semiannual examination by the medical rather than by the obstetric attending staff. The object of the study has been to find out what type of woman is subject to the condition during pregnancy and what pathologic changes are present not only at the time of the toxemia but in the years following. Of importance also are the life expectancy of these patients, the cause of death and the observations at necropsy. Our observations suggested that the toxemias may not be isolated, idiopathic states but that they are possibly related to certain common general medical conditions. That this suspicion may have some foundation is suggested by important statistical