In the first ever theoretical treatment of the environmental justice movement, David Schlosberg demonstrates the development of a new form of `critical' pluralism, in both theory and practice. Taking into account the evolution of environmentalism and pluralism over the course of the century, the author argues that the environmental justice movement and new pluralist theories now represent a considerable challenge to both conventional pluralist thought and the practices of the major groups in the US environmental movement. Much of recent political theory has been aimed at how to acknowledge and recognize, rather than deny, the diversity inherent in contemporary life. In practice, the myriad ways people define and experience the `environment' has given credence to a form of environmentalism that takes difference seriously. The environmental justice movement, with its base in diversity, its networked structure, and its communicative practices and demands, exemplifies the attempt to design political practices beyond those one would expect from a standard interest group in the conventional pluralist model.