Using two versions of the A-not-B task, memory and response inhibition were assessed in 17- to 24-month-old children with surgically corrected single-suture craniosynostosis (cases) and unaffected children (controls). Children's development and language were initially assessed on average at 6-7 months of age and again at this second visit. Cases and controls performed at equivalent levels on average, with cases performing slightly better than controls on several of the variables measured. However, fewer cases than controls were able to complete the more challenging of the two tasks, which may have predictive significance for later functioning. Children's age and cognitive ability were related to successful performance on the A-not-B task. Among cases, age of cranioplastic surgery was unrelated to performance. Our findings suggest that children with single-suture craniosynostosis show normal development of visual memory and response inhibition in the age range studied here.