We have compared identification and imitation of a synthetic vowel continuum varying from [æ] to [ɑ] among Finnish speakers. Results indicate that special practice is needed for listeners to monitor only the sensory information in imitation and to bypass what is learned and stored in long-term memory. We had three kinds of participants: preschool children, naïve adults, and phoneticians. All the groups were able to identify the vowels systematically in the listening experiments, although individual differences were found in the location of the category boundary. Adults performed better than children in goodness rating. The experts rated goodness accurately. After the listening tests, the participants imitated the same stimuli. In this condition imitation proved to be categorical among children and naïve adults as the previous studies have suggested. Phoneticians could imitate gradually changing vowel qualities without any abrupt changes reflecting the way how the continuum was categorized into phonemes.