Recent evidence suggests that children with relatively minor hearing impairments may be at a developmental disadvantage. A survey of over 42,000 students was conducted and children with unilateral hearing losses were identified on the basis of audiometric testing. A comparison of the standardized achievement test scores obtained by the unilateral hearers, using class and national norms with a sibling control group, yielded no significant differences although the hearing-impaired group scored lower on all subscales. There were sex differences observed, however, with male unilateral hearers performing significantly better than females on several subscales. Although the results indicate little educational disadvantage accompanying unilateral losses in this sample of children, in the absence of more definitive evidence, it would be prudent to consider a unilateral loss as a 'risk factor' for the production of developmental problems.