Mapping controversies on environmental issues is a good starting point for learning about their complexities. One way to accomplish this task is through discourse mapping. Discourses are shared ways of understanding the world. Diverse values, vested interests, critical perspectives and insights are embedded within discourses. These both reflect and construct attitudes towards the natural world. Discourse mapping is an interpretative method that can reveal political strategies, ideologies and tactics. In displaying the distinctions between discourses, the outlines of controversies are clarified. This paper contributes to a theory of knowledge visualization and presents two discourse mapping projects (one completed project and one that is in its initial stages) on environmental themes: Mapping Climate Communication (2014) and Mapping Degrowth (2016 – 2017). Knowledge visualization captures meaning lost with more reductive visualization methods.