This chapter addresses the orthodox economics paradigm, and the reasons why its theoretical underpinnings might be especially challenged by the environmental problems that we are facing. We begin by identifying how its particular view of the world deals with environmental issues. Economics has its own particular jargon and method (involving a considerable amount of mathematics and graphs), and, although I have kept these to a minimum, this may prove challenging to some readers; I hope that the argument will still be clear. This chapter presents the bones of the neoclassical approach and the proposals from the economics mainstream in response to the environmental problem. Environmental economics, which is covered in the following chapter, shares many of the assumptions and methods of the neoclassical approach. To some extent, the division of this body of thought into two chapters is pragmatic, although it seems fair to say that the theories and theorists covered in Chapter 4 have made the environment central to their study, and that their work tends to have emerged since environmental problems came to the fore, from around the late 1960s onwards.