The present study investigates the effect of high variability phonetic training (HVPT) on the discrimination of second language (L2) vowel contrasts by adult speakers who live in a country where the L2 is dominant. The same subjects who participated in a previous discrimination task were trained in the discrimination of four L2 vowel contrasts which were relatively difficult for this population of learners. Both the post-test and the generalization test showed significant improvement in the discrimination of most vowel contrasts (both stressed and unstressed). The findings suggest that HVPT may facilitate the formation of robust L2 phonological representations even for learners who live and are educated in an L2-dominant environment, dissolving in that way the perceptual confusions which emerge from first language interference. Finally, important implications are made for the implementation of HVPT in L2 classrooms.