Mainstream L2 phonology models do not include predictions concerning how the prosodic structure interacts with the acquisition of segments. However, many studies have shown that the realization of pitch accents or melodic contours associated to prosodic boundaries results in the hyperarticulation of segments in correspondence of such prosodic boundaries. Our goal is to provide empirical evidence for the positive effects of prosodic prominence on the acquisition of challenging L2 French soundsThe prosodic-phonetic interface has been largely underestimated in second language acquisition. Few studies have investigated whether prosodic prominence may serve as an optimal context for learners to extract information on the acoustic properties of new sounds, which may then be reflected in more accurate productions. In this paper, we report the acoustic patterns of L2 French vowels produced in two different prosodic conditions: (1) in word internal position (unaccented), (2) in initial and final boundaries of Accentual Phrases and Intonation Phrases. We analyzed oral productions by 40 participants: 10 French native speakers and 30 L2 French learners with L1 Spanish, L1 English and L1 Italian (10 each). We extracted acoustic parameters for ~15k vowels and calculated the degree of acoustic overlap via Pillai scores for the following triplets: