This study was designed to establish the specific communicative function of both low (L*) and high (H*) pitch accent onsets with high rising tunes (HRTs), earlier established as a feature of Australian English. The data consisted of the dialogues of four female and four male adolescent speakers who were recorded while participating in the Map task. The discourse analysis involved the application of Pierrehumbert & Hirschberg's compositional theory of tune meaning. The study appears to support key aspects of Pierrehumbert & Hirschberg's theory: the results show overwhelmingly that the speakers used high (H*) pitch accents with new information and low (L*) pitch accents with information that was already part of the speaker and hearer's mutual beliefs. The findings suggest that the individual tones in a HRT each contribute to the overall meaning of an intonation contour, and that a close examination of intonation features within a developing communication context is crucial to understanding intonational meaning.