Green Theory ROBYN ECKERSLEY O Chapter contents • Introduction • The emergence of green theory • The transnational turn in green theory • The greening of IR theor • Case study • Conclusion C Reader's guide This chapter explores the ways in which environmental concerns have influenced International Relations (IR) theory. It provides a brief introduction to the ecological crisis and the emergence of green theorizing in the social sciences and humanities in general, noting its increasing international orientation. and then tracks the status and impact of environmental issues and green thinking in lR theor. It shows how orthodox IR theories, such as neorealism and neolibralism,l have constructed envir onment problems mereiy as a 'new issue area' that can be approached through pre existing theoretical frameworks . These approaches are contrasted with green IR 1he· ory, which challenges the state-centric framework, rtionalist analysis, and ecological blindness of orthodox IR theories and offers a range of new green interpretations of International justice, dlopment, modernization, and �ity. The case study of climate change is explored to highlight the diversit} of tretical approaches, including the distinctiveness of green approaches, in und. ding global environ· mental change.