Some of America's most severe environmental inequalities occur in its cities. This was especially the case in the decades immediately following World War Two, when white flight, deindustrialization and disinvestment, urban renewal and highway construction led a massive increase in particular types of urban environmental issues, especially in the country's older industrial cities. In response, city residents organized a series of highly local, grassroots but robust movements to address immediate harms but also create more just and livable cities. This chapter tells the story of that activism, while also placing it within the context of the longer history of urban environmental activism in the United States, the environmental movement and the emergence of environmental justice activism in the 1980s.