In this article, we offer a normative analysis of environmental politics through the lens of civility. First, we explain what civility is by identifying its three key dimensions: civility as politeness, moral civility and justificatory civility. We then examine various instances of environmental politics and activism through the lens of civility, by focusing on the complex intersections between its three dimensions as well as the hierarchical relationship that exists between them, with moral civility taking precedence over justificatory civility and the latter over civility as politeness. This analysis, we argue, can help us to formulate more nuanced judgements about the desirability of different instances of civil and uncivil environmental politics and activism, and to develop educational strategies for preparing policymakers, environmental activists and citizens more generally to be civil participants in environmental politics.