Bilateral renal agenesis is a relatively uncommon anomaly. Of some 317 known cases, about 75% were male. The occurrence of this anomaly in siblings has been described twice, and both pairs were male. This report provides the first description of bilateral renal agenesis in two consecutive female siblings, both of whom were additionally unusual in having normally developed müllerian duct structures. Breech presentation, prematurity, low birth weight, Potter's facies, and anomalies of the lower extremities were common to each. At autopsy both infants manifested bilateral renal and ureteral agenesis, and hypoplasia of the urinary bladder, but the vagina, uterus, fallopian tubes, and ovaries were of expected size and normally developed. One infant had severe hypoplasia of the lungs. Etiological considerations leading to agenesis of nephric tissues have been discussed in relation to these findings.