Eye-gaze plays an important role in face-to-face communication. This chapter presents research on exploiting the rich information contained in human eye-gaze for two types of applications. The first is to enhance computer mediated human-human communication by overlaying eye-gaze movement onto the shared visual spatial discussion material such as a map. The second is to manage multimodal human-computer dialogue by tracking the user’s eye-gaze pattern as an indicator of user’s interest. We briefly review related literature and summarize results from two research projects on human-human and human-computer communication.