Argumentation can be defined at different levels and serve different purposes, but its role in knowledge understanding and construction has given it a central place in education, particularly at tertiary level. The advent of computer-supported text-based conferences has created new sites where such educational dialogues can take place, but the quality of the interaction and whether it is serving its educational purpose is still uncertain. This paper reports on a framework of analysis that has been developed to illuminate the arguing process within an asynchronous electronic conferencing environment, showing how it is both similar to, and different from, argumentation in the more traditional forums of multi-party, face-to-face discussion and traditional written essays. The framework develops earlier work by the authors and is applied to two electronic conferences within the same postgraduate course, comparing overall patterns of argumentation. Findings are presented on the extent to which the technology of electronic conferencing shapes and supports students' participation in academic literacy practices relating to argumentation, proposing, at the same time, that the teaching strategy adopted by the lecturer is also an important variable.