I design algorithms for real-time intelligent interactive systems that coordinate with user actions that are beyond spoken languages, including non-verbal behaviors to achieve effective and natural communications. In particular, I optimize human-machine communication via studies of multimodal sensing and analysis, speech and natural language processing, machine learning and human-computer interaction. The central focus of my dissertation research is to bring together all the areas above to design, implement and deploy end-to-end real-time interactive intelligent systems that are able to plan globally considering interaction history and current user actions to achieve better user experience and task performance. Meanwhile, I enjoy collaborating with researchers with different backgrounds on interdisciplinary research in all area of science, such as health care, education and robotics.