This study used a referential communication task to investigate the effectiveness of elderspeak, a speech register targeted at older listeners. The tasks required the listener to reproduce a route drawn on a map or array of dots, following the speaker's instructions. Dyads of young-young, old-old, and young-old adults were compared with regard to measures of fluency, prosody, grammatical complexity, semantic content, and speaker and listener style. Although the older speakers showed little variation in response to listener age or task difficulty, the young speakers adopted a simplified speech style when addressing the older listeners. These simplifications may have been triggered by the verbal responses of the older listeners. Older listeners did benefit from these speech adjustments with regard to the accuracy of their maps and dot patterns. Despite the effectiveness of the young adults' speech adjustments, older adults reported more expressive and receptive problems when interacting with the young adults. Copyright © 1995 Sage Publications.