When compared to native-speaker language ‘targets’, second language (L2) speakers are known to exhibit within-speaker variation in their L2 language performance according to the identity of their interlocutor (Beebe & Zuengler, 1983), the topic that is being discussed (Dolgova Jacobsen, 2008), or both (Rampton, 2011). However, previous studies have rarely applied the same methodology to different first language (L1) groups and have rarely used data from a range of speakers, so they have been unable to explore differences between speaker groups. This paper examines situational style-shifting in L2 speakers of New Zealand English in two groups of speakers, one with Korean as their L1 and the other with German as their L1. Participants were recorded in three different settings: discussing family, discussing work, and in an authentic service encounter. Male and female speakers showed similar patterns, and all were found to exhibit stylistic variation in their production of English vowels such that tokens were most nativelike in service encounters, followed by discussion of work and then family. This pattern was more robust for the Korean L1 speakers than for the German L1 speakers, which is explained by different social and linguistic histories of the two groups in New Zealand. This paper adds to the current understanding of sociolinguistic variation in L2 speakers by applying audience design (Bell, 1984) and identity construction (Eckert, 2000) accounts to L2 speakers’ production of vowels.