This chapter aims to provide an introduction and outline of key elements and debates surrounding ecocide as an emergent concept within the field of criminology. It explores the development and definition of the concept of ecocide, its consequences, the link between ecocide and violence, and the relationship between ecocide and foreknowledge of such harm. Ecocide refers to significant destruction, degradation, and diminishment of the environment, in whole or in part as a result of human acts or omissions. Establishing the crime of ecocide is motivated by the need to respond to a singularly important trend: the existing planetary environment is rapidly being destroyed. Climate change and the gross exploitation of natural resources are leading to the general demise of the ecological status quo – and, hence, increasing the need for the crime of ecocide. The causes of ecocide reside in dominant systems of production and consumption that are under the control of transnational corporations and powerful nation-states.