Central nervous system (CNS) involvement often occurs during an acute episode of Hemolytic Uremic Syndrome (HUS). Published reports describe severe CNS sequelae in 3 - 10% of survivors. The possible occurrence of mild CNS effects was rigorously investigated for the first time in this multi-centre case-control study carried out at six Canadian tertiary care hospitals within the reporting network of the Canadian Pediatric Kidney Disease Research Centre. Ninety-one HUS survivors without severe CNS sequelae were compared with hospital controls pair-matched on age, sex, socio-economic status, first language and history of acute hospital admission. Cognitive, academic and behavioural tests were administered by psychometrists blinded to patient-control status. No differences were obtained on cognitive nor academic measures [e.g., HUS vs controls: Full scale IQ, 104.9 (SD 13.6) vs 106.2(12.9), p =.45; WIAT math, 101.7 (11.9) vs 99.8 (15.4), p =.40]. HUS survivors did not show any deficits on behavioural ratings. Markers of disease severity yielded a few statistically significant correlations with outcome measures but these were too small to have clinical importance. The results of this large and carefully controlled study indicate that children who make an uncomplicated recovery from an acute HUS episode are not at heightened risk for mild CNS sequelae.