Coincidental increases in online instruction at institutions of higher education and in online social networking generally in the U.S. have created opportunities for research into how digital interpersonal connectivity affects online learning. This study examined interactive webcasts, or webcasts plus chat, that were part of an online undergraduate course covering Internet knowledge and skills at a large public university. Symbolic interactionism served as the theoretical framework for explicating interactive webcasts as useful online learning environments by exploring the complex processes that instructional staff employed to manage their actions and interactions as moderators in the webcasts and chats. A constructivist grounded theory approach guided the collection and analysis of empirical data in the form of webcast media and transcripts, chat logs, students‘ reflective writing, and semi-structured, intensive interviews with instructional staff. From the study emerged theoretical categories in three tiers related to a generalized moderator process called minding the verge: moderators minded the verge in three conditions of interaction– converging, attending, and diverging; in three loci of interaction – webcasts, chats, and webcasts+chat; and through six actions of moderating – bonding, orientating, guiding, tending, validating, and branching. The results of this study provide moderators for the course with insights into their actions in the interactive webcasts and with concepts moderators can use to explore how to manage interactive webcasts more effectively. Beyond effecting substantive changes to interactive webcasts for the course, the study may guide others who wish to pursue further studies of webcasts+chat as they occur in the course or elsewhere, or of other mixed-media environments, or who wish to adopt mixed-media environments for instruction. Other potential areas for research that emerged from this study include the affective states of participants in the webcasts+chat and the use of affective devices, such as emoticons and abbreviations, for showing affective states; the effect that format has on the efficacy of webcasts+chat used for computer-mediated instruction; and the processes students employ to manage actions and interactions in the webcasts and chats. / text