Acute renal failure, either as a primary disorder or as a secondary complication of various clinical conditions, has received intensive attention from various investigators during the past decade. The problems inherent in the prevention and management of this clinicopathological entity have been of special concern to the obstetrician, since, in almost all large series reported, cases with obstetric relationships have comprised a large proportion of the total group under study. The present study is concerned with the etiological factors, clinical course, and management of a group of patients in whom acute renal failure occurred as an obstetric complication. The discussion is directed not toward individual case reports but rather toward consideration of some of the general aspects of the problem as it presented itself in this series. GENERAL CAUSES OF RENAL FAILURE Multiple and varied factors usually enter into the causation of acute urinary suppression in an obstetric patient. In