Prosody is an important aspect of speech that contributes to expressiveness and intelligibility of the speech. Quantitative modeling of speech prosody is a key in the advancement of speech science and technology. Based on a previous successful research collaboration, the proposed research will be a major systematic effort to develop an “articulatory-functional” quantitative model of speech prosody and integrate into it meaningful communicative functions. The project has three overall objectives: 1) to further develop the qTA model, 2) to conduct a comprehensive test of the developed model and investigate the form of communicative functions in two major languages (English and Mandarin), and 3) to develop a general-purpose prosody research tool based on the developed model. The outcome of this research will facilitate the research and development of speech science and technology, and enhance the applicability of practical systems that make use of prosodic models.