In this article, using a posthumanist and Deleuzian vocabulary, we problematize theanthropocentric approach within communication theory that at present is setting thetheoretical ground for environmental communication. We argue that ‘anthropocentrism’has caused humans to situate humanity at the top of an assumed environmental hierarchy.Consequently, humanity has given itself the right to interpret the world according to itsown standard. This, in turn, has consequences for what is called the environment,including its marginalization and exploitation.To address this issue, we maintain that environmental communication is in need of aposthuman theoretical elaboration that allows for a post-anthropocentric turn and enablesan alternative radical approach to environmental communication theory. Our mainargument is that the idea of processuality allows us to work with relationality as aconcept within environmental communication theory. Relationality gives rise to thecommunicative actions that are put in motion by environmental communication theory.In traditional environmental communication research, environmental issues areunderstood as expressions of discourses or systems. We suggest, in response, thatenvironmental issues, as posthuman communicational processes, are crucial forunderstanding sustainable development as a set of practices. Posthuman or posthumanisttheory, we argue, makes possible a turn from an androcentric ideal to a postanthropocentricstance within environmental communication. This lets us develop theconcept of “sustainable development” and its practices as relating to both material andethical matters. Environmental communication thus becomes a function in whichknowledge provides the necessary abstraction for engaging in posthuman and postanthropocentriccommunicative actions.