This research considers how professional participants in a non-formal self-directed learning environment (NFSDL) made use of self-directed learning activities in a blended face-to-face and on line learning professional development course. The learning environment for the study was a professional development seminar on teaching in higher education that was offered to ten novice professors over the course of one academic year in a western Canadian research-intensive university. Autonomous activities were compared to on line and face-to-face social networking activities, and the effect of structure on the amount and type of self-directed engagement will be examined. We consider whether there is a need to adapt basic theory on formal virtual learning communities to understand self-directed learning and pedagogical practices in non-formal on line learning environments. (Contains 6 tables.)