This paper traces aspects of the development of a ‘green’ criminology. It starts with personal reflections and then describes the emergence of explicit statements of a green criminological perspective. Initially these statements were independently voiced, in different parts of the world but they reflected shared concerns. These works have found unification as a ‘green’, ‘eco-global’ or ‘conservation’ criminology. The paper reviews the classifications available when talking about not only legally-defined crimes but also legally perpetrated harms, as well as typologies of such harms and crimes. It then looks at the integration of ‘green’ and ‘traditional’ criminological thinking before briefly exploring four dimensions of concern for today and the future.