This dissertation argues for expanding a practice approach to media combined with cultural studies to address the continuing problems of technological deterministic tendencies in the field of alternative, radical and citizen’s media research. Applying this approach specifically, this study offers the concept of movement media as an organized set of practices that creates spaces of action to connect what is separated and mediate cultures for social change. Drawing on twelve months of online and off-line fieldwork, the dissertation develops an ethnographic account of movement media in the Miryang environmental struggle against the Korea Electronic Power Corporation’s 765,000-voltage transmission line construction. Focusing on the protest participants’ primary practices—sit-ins, candlelight vigils, and gifting food—as well as the corporation’s monetary and temporal practices, the dissertation analyzes what movement media were, why they appeared, how they developed, persisted or transformed, and what the consequences of movement media were in forming or transforming political culture, thereby promoting activism around energy issues. Based on this ethnographic case study, the dissertation contributes to ways of understanding the complexities of communication processes in movement media that are deeply entangled with a locale’s cultural, historical, and political-economic contexts.