The neural bases of prosody during the production of literal and idiomatic interpretations of literally plausible idioms was investigated. Left- and right-hemisphere-damaged participants and normal controls produced literal and idiomatic versions of idioms ("He hit the books.") All groups modulated duration to distinguish the interpretations. LHD patients, however, showed typical speech timing difficulties. RHD patients did not differ from the normal controls. The results partially support a differential lateralization of prosodic cues in the two cerebral hemispheres [Van Lancker, D., & Sidtis, J. J. (1992). The identification of affective-prosodic stimuli by left- and right-hemisphere-damaged subjects: All errors are not created equal. "Journal of Speech and Hearing Research," 35, 963-970]. Furthermore, extended final word lengthening appears to mark idiomaticity. (Contains 2 figures.)