This study examined the factors and peer facilitation techniques that influenced students' participation in sustained asynchronous online discussion. A case study approach was used, with data collected through interviews, questionnaires, and online discussion transcripts. The findings revealed that factors such as interesting topic, familiarity with topic, and limited time influenced students' participation in online discussions. Peer facilitation techniques that students perceived to influence their choice of discussion threads to participate in included techniques such as "thanking others" and "encouraging contribution." Interestingly, the order of perceived impact of these peer facilitation techniques and the actual order of frequency of usage of these techniques in the online discussions, as observed in the online discussion transcripts, was not the same. Reasons for this discrepancy were discussed. (Contains 5 tables and 6 figures.)