What constitutes successful practice for supervision of postgraduate students at an Open and Distance learning institution? In this article I describe a limited experiment in on-line teaching using a group of postgraduate students at the University of South Africa (Unisa). While the experiment has obvious limitations including the short time in which it has been running, the small size of the group and the experience of only one facilitator, it may have large ramifications in terms of potential online learning opportunities in the near future. The aim of this article is to indicate the relative importance of technology itself in relation to student interaction online, as is suggested by Brand (1997): "Evaluating the role of technology itself on learning has merit, but technology does not operate independently to create a learning environment. Student interaction online, like student interaction in face-to-face classrooms, is a critical component of the learning context." I hope to show that crucial moments in communication, interaction, reaction and non-reaction amongst the six students, myself and observers, have significant consequences for online teaching and learning amongst larger groups of students. As increasing numbers of college-level courses are developed for delivery via the World Wide Web, pressure grows to identify components of online learning environments that contribute to or support learning. Much of the research focus in online education has been on technical characteristics such as platforms, download speed, engaging links, streaming audio and streaming video. Evaluating the role of technology itself on learning has merit, but technology does not operate independently to create a learning environment. Student interaction online, like student interaction in face-to-face classrooms, is a critical component of the learning context. This appears to be especially true for one of the largest groups served by online classes, non-traditional or adult students, whose expectations are likely to include dynamic interaction with others and learning constructed through discussion (Brandt 1997). (Contains 1 figure and 7 notes.)