This thesis investigates the ability, exercise and consequences of business power in environmental conflict in advanced capitalist society. Research into this subject has tended to fall into either of two camps; system-wide theoretical studies from within political economy or narrower empirical studies by neo-pluralist scholars. It is argued there is a need to reconcile these levels to see how the various mechanisms of influence coincide. The critical realist philosophy of science is used to clear the path for the project, detailing, among other things, an understanding of the nature of social being and of social scientific investigation. The various strands of literature on business power and the environment are reconciled in a two stage analytical framework. The first part of that framework deals with the dilemma of theorising about class in environmental conflict. The solution to that problem is found in value-form. This approach allows structural connections to be made between socioeconomic class and types of substantive value relations with the natural world. The second part of the framework deals with the issues of power and politics. It integrates the wider political economy approach and the narrower mechanisms of business power studied usefully by neo-pluralists. Two in-depth historical case studies of environmental conflict are carried out; the Black Head conflict over a quarry operation near Dunedin, and the much larger Whanganui River Minimum Rows dispute, both throughout the 1980s. At the end of each study the principles of the analytical framework are investigated in turn. It is ultimately concluded that the ability of business to dominate within this context is not absolute, yet it is real and pervasive. Such dominance poses a serious impediment to the achievement of sustainable relationships with the natural world, and the ability of people to participate in decision-making in respect to their environments.