The study investigates predictors of the acquisition of selected English phonemes in a foreign language context. Czech students' pronunciation was diagnosed by two tests; their ability to produce seven selected phonemes was assessed. Furthermore, data regarding the students' learning histories was obtained through a questionnaire. Then a multiple regression analysis was conducted in order to identify predictors of the acquisition of the selected phonemes. The analysis uncovered several factors, the most significant being preschool exposure to English and positive attitudes to English in adolescence, which appeared to influence the subjects' pronunciation positively. Interestingly, several factors which relate to learning English at school appeared to exert a negative influence on the acquisition of the selected phonemes. Furthermore, besides the importance of long-term exposure to English starting before the age of six, the study also underscored the importance of metacognition in relation to autonomous learning.