Environmental justice (EJ) is the struggle for access to a safe and healthy environment free from pollution and for access to the environmental resources needed for survival, well being, and social reproduction. The term environmental justice was originally born in the United States from the resistance of African American communities linked to the civil rights movement protesting toxic dumping and the siting of hazardous facilities in their communities. Scholars soon joined activists, concerned citizens, and religious leaders and communities to systematically document injustices and demonstrate that “pollution is not color blind” by demonstrating that disparities of environmental exposure exist among racial lines. EJ provided a powerful challenge to the mainstream current of the environmentalism definition of environment and nature, which focused on wilderness conservation and natural areas, such as national parks and endangered species. Environmental justice considers the inseparability of the environment from everyday life and redefines the environment as “the places where people live, work, and play.” Over time, the environmental justice framing has continually expanded to engage with multiple spatialities and forms of inequalities and has brought a far wider range of issues under the umbrella of what is the environment. In the early 21st century, environmental justice can best be understood as a shared frame and coalition of anti-toxics; labor, civil rights, indigenous, environmental, and feminist movements; and radical scholars, among others. Their common conviction is that environmental problems are largely structural and political issues that cannot be solved apart from social and economic justice and that these call for a transformative approach and the restructuring of dominant economic models, social relations, and institutional arrangements. From an initial focus on the socio-spatial distribution of “bads” (emissions, toxins) and then “goods,” (parks, green spaces, services, healthy food), environmental justice in the early 21st century encompasses a huge array of issues and has increasingly taken on transnational and transdisciplinary character and has become a meeting place for action-research among a growing network of activists, scholars, and nongovernmental organizations. EJ can be said to be a “theory in practice,” in constant coevolution and redefinition by many activist groups, international coalitions, and intellectuals.