This article examines the perception of four English vowels (/i, i, ε, æ/) by adult native speakers of German. From the standpoint of German, it appears that English /i, i,ε/ are perceptually similar, if not identical, to German /i, i, ε,/ whereas /ε/ is a “new” vowel for German learners of English. The role of foreign language experience in the perception of second language vowels was examined through labeling responses to members of synthetic continua (beat-bit, bet-bat) in which vowel duration and spectrum were varied factorily. The subjects were relatively experienced and inexperienced second language (L2) learners and a monolingual English control group. The results suggest that L2 experience did not affect perception for the continuum with the two “similar” vowels /i/ and /I/. However, for the continuum involving the “new” vowel /æ/, the experienced Germans more closely resembled the native English speakers than the inexperienced Germans. The predominant use of duration cues in differentiating the English /ε/–/æ/ contrast by the inexperienced Germans suggested that when spectral cues are insufficient to differentiate an L2 vowel contrast, duration will be used. © 1990, Cambridge University Press. All rights reserved.