To test the effects of a vertical versus a horizontal arrangement of brief structured text entries on known-item search times, 2 groups of 12 women university graduates with mean ages of 71 years and 33 years respectively took part in an experiment. Subjects were classified as either having or not having library reference experience. They were asked to locate and answer factual questions concerning thesaurus entries arranged in each format. The important data unit for analysis was the difference in time for each subject rather than the actual times. Results indicated that differences in search times were proportionately the same for both age groups. Significantly slower search times occurred under the horizontal arrangement, and no participant judged the horizontal arrangement to be easier to use than the vertical arrangement. Those younger people with reference experience preformed more slowly with horizontal presentation than did those younger people without experience. No effect of age was found upon disorientation caused by unanticipated arrangement of test entries.