This study assessed the efficacy of a pronunciation training program that provided fundamental frequency contours as visual feedback to native English speakers acquiring Japanese pitch and durational contrasts. Native English speakers who had previously studied Japanese for 1-5 years in the United States participated in training using Kay Elemetrics' CSL-Pitch Program. The training materials were words, phrases, and sentences that contained Japanese pitch and durational contrasts. During training the subjects practiced matching the fundamental frequency contours of Japanese-native models shown on a computer screen. The subjects' ability to produce and to perceive novel Japanese words was tested in two contexts, that is, words in isolation and words in sentences, before and after training. Their ability was compared to that of a native English control group that had previously studied Japanese for 1-5 years but did not participate in the training. The trained subjects improved significantly for words in sentences as well as for words in isolation. Also, the trained subjects improved significantly in perception as well as in production. These findings suggest that the pronunciation training program developed and used here was effective in improving the ability of native English speakers to produce and perceive Japanese pitch and durational contrasts.