This thesis raises the question of how contemporary democratic decision making processes might be structured so that they adequately attend to environmental values. As such, it engages with the growing interest in connections between environmental politics and ethics and democratic theory and practice. A conception of value pluralism is offered and attention is drawn to the variety of ways in which it is possible to value the nonhuman world. When judging ethically and politically, we do so from particular perspectives, appealing to a plurality of values which are at times incommensurable and/or incompatible. Conflict and indeterminacy are often endemic. Value pluralism can be seen as a challenge to approaches in moral philosophy and environmental ethics which aim to develop a monistic ethical theory, a single comprehensive theory that systematically orders the different values we hold. Decision making techniques such as cost-benefit analysis are insensitive to such value pluralism. The attempt to extend neo-classical economic techniques to include environmental costs and benefits misrepresents the values we associate with the nonhuman world. Procedural liberal theory and liberal representative institutions fail to attend to value pluralism, particularly in the environmental realm. This failure is central to the growth of political alienation amongst citizens and the lack of trust in contemporary forms of political authority. This is particularly evident in current responses to decision making in the transport sector. A conception of deliberative democracy is offered that is sensitive to value pluralism. Such a conception offers the possibility of more legitimate forms of political authority and the development of trust. Attention is drawn to the need to develop the political space in which environmental values can be articulated and defended.