A literature review was conducted to summarize current understanding of the effects of severe chronic renal failure (CRF), when present from infancy, on neurologic development. Data were obtained from the results of 95 examinations performed in 85 patients, most of whom had been studied after 12 months of age, or following initiation of maintenance dialysis or successful transplantation. CRF was diagnosed at birth or during the neonatal period in 71.7% of these patients; serum creatinine concentrations or calculated clearances were greater than or equal to 2.0 mg/dl (177 mumol/l) or less than 15 ml/min per 1.73 m2, respectively, in 75.8%. Head circumferences were greater than 2 standard deviations below the mean for age in 33 of 51 (64.7%) patients. Developmental delay was identified in 63.2% of all cases, and in 29 of 48 (60.4%), 16 of 19 (84.2%), and 4 of 13 (30.7%) patients studied while receiving conservative management or maintenance dialysis, or following successful transplantation, respectively. Moderate to severe delays were commoner for gross motor and language development. No significant relationships could be identified between age or severity of CRF at diagnosis and either the prevalence or severity of developmental delay. Other factors that may have contributed to observed developmental delays are also discussed, including aluminum loading, hyperparathyroidism, undernutrition, and psychosocial problems. New data are presented and discussed, and recommendations for future studies provided.