Over the course of nearly thirty years, the environmental justice movement has changed the politics of environmental activism and influenced environmental policy. In the process, it has turned the attention of environmental activists and regulatory agencies to issues of pollution, toxics, and human health as they affect ordinary people, especially people of color. This book argues that the environmental justice movement has also begun to transform science and engineering. The chapters present case studies of technical experts’ encounters with environmental justice activists and issues, exploring the transformative potential of these interactions. Technoscience and Environmental Justice first examines the scientific practices and identities of technical experts who work with environmental justice organizations, whether by becoming activists themselves or by sharing scientific information with communities. It then explore scientists’ and engineers’ activities in such mainstream scientific institutions as regulatory agencies and universities, where environmental justice concerns have been (partially) institutionalized as a response to environmental justice activism. All of the chapters grapple with the difficulty of transformation that experts face, but the studies also show how environmental justice activism has created opportunities for changing technical practices and, in a few cases, has even accomplished significant transformations.