Auditory brainstem-evoked responses were recorded from 14 children with clinical and radiological evidence of brainstem glioma. Responses were abnormal in all cases. The findings were consistent with intrinsic brainstem lesions in all except one case with a glioma, which was shown to be located predominantly in the medulla oblongata. Seven of the children had more than one test and changes in the responses paralleled clinical changes in all except the case with glioma of the medulla. The usefulness of auditory brainstem-evoked responses as an aid in diagnosing and monitoring changes in brainstem gliomas is discussed.