To avoid potential miscommunication resulting from structural ambiguity, speakers and listeners often rely on differences in prosodic realization. For instance, the sentence "Jennifer blackmailed the boss of the clerk [who was dishonest"][subscript RC'] is realized with different prosody depending on the attachment of the relative clause (RC) -- whether it modifies "the clerk" or "the boss." Korean is typologically different from English in both its syntactic structure and its prosodic structure, but it exhibits similar ambiguities associated with high vs. low attachment of RC. This dissertation research had three goals. First, it compared English and Korean speakers' use of prosody for the resolution of RC attachment ambiguity in their production. Second, it provided an account of the prosodic disambiguation patterns in the two languages with a constraint-based approach to the syntax-prosody interface. Third, it compared the production and processing of ambiguous English sentences by native speakers of English and by Korean-English second language (L2) speakers to examine the influence of native language on L2 prosody. Results from a production experiment showed that English speakers used both prominence and boundary cues, while Korean speakers used only boundary cues. The Korean-English L2 speakers' productions demonstrate that they have learned to use phonological categories such as pitch accents and de-accenting, although their use of phonetic cues to realize these categories was still different from native English speakers, and that they did not make use of prosodic boundaries. The pattern that native productions of both English and Korean showed an insertion of an intonational phrase boundary for disambiguation is analyzed as the result of a context-specific sub-grammar for disambiguation with an undominated constraint CONTRAST-S. Thus, the lack of boundary cue use by English L2 speakers indicates that they have not successfully learned this sub-grammar for ambiguity avoidance in the target language. Results from a processing experiment showed that English speakers weight pause and pitch cues more heavily than lengthening and intensity cues in the comprehension of RC attachment ambiguity, while for Korean-English L2 speakers, pause was the most heavily weighted cue. This indicates that Korean-English L2 speakers' processing is more influenced by their first language prosody than their production. The findings in this dissertation shed light on the syntax-prosody interface in languages with typologically different prosodic systems and the production and processing of prosodic cues for disambiguation by L2 speakers. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]