Two experiments were performed in which blind Ss, sighted Ss working in the dark, and sighted Ss working in the light were compared as to their efficiency on an auditory watchkeeping task. Absolute and differential auditory thresholds were measured in both experiments, and in the second experiment the groups also underwent a signal detection session under alerted conditions. There was some inconsistency as to relative performance of the sighted groups, but in both experiments the blind Ss were superior on the auditory watchkeeping task as to signals detected and effective sensitivity (d'). < This difference was not attributable to a difference in auditory sensitivity or to a criterion adopted for responding. The groups in the second experiment did not differ significantly on the alerted signal detection task. Blind Ss' superior detection efficiency was attributed to the transfer of practiced variables related to more efficient utilization of auditory information.