This thesis offers an immanent critique and reconstruction of green moral and political theory. In chapter 1, the critical-reconstructive approach and spirit of the thesis is outlined in terms of contributing to the process of developing a green political theory that is different from 'ecologism' or ideological accounts of green politics. In chapter 2, deep ecology is critically interrogated in terms of its metaphysical (2.3) and psychological claims (2.4). Its view of the 'ecological crisis' as a 'crisis' of western culture is criticised as is its a priori defence of environmental preservation over the human productive use of nature. While its ecocentrism is rejected as the normative basis for green politics, its concern with virtue ethics is held to be an important contribution. In chapter 3, a self-reflexive version of anthropocentrism is developed as the most appropriate moral basis for green politics. Some naturalistic arguments are presented in order to support 'speciesism', and defend it from claims of arbitrariness and as being akin to sexism or racism. Arguments centring on demonstrating the tenuous character of the differences between humans and nonhumans are argued to neglect the fundamental moral significance of the difference between 'human' and 'nonhuman'. I argue that an ethic of use, understood as a reflexive mode of interaction with the nonhuman world, is a defensible form of anthropocentrism for green political purposes. The basis of this reflexive anthropocentrism turns on the claim that while human interests are a necessary condition for justifying a particular human use of nature, it is not a satisfactory one. Issues pertaining to the 'seriousness' of the human interest which is fulfilled are held to be important in distinguishing 'use' from 'abuse'.