This paper concerns non-verbal communication, and describes especially the use of eye-gaze to signal turn-taking and feedback in conversational settings. Eye-gaze supports smooth interaction by providing signals that the interlocutors interpret with respect to such conversational functions as taking turns and giving feedback. New possibilities to study the effect of eye-gaze on the interlocutors' communicative behaviour have appeared with the eye-tracking technology which in the past years has matured to the level where its use to study naturally occurring dialogues have become easier and more reliable to conduct. It enables the tracking of eye-fixations and gaze-paths, and thus allows analysis of the person's turn-taking and feedback behaviour through the analysis of their focus of attention. In this paper, experiments on the interlocutors'non-verbal communication in conversational settings using the eye-tracker are reported, and results of classifying turn-taking usin...