The concept of environmental justice has its origins in the United States in the 1980s when it was used to describe the unequal impact of industrial pollution on racial minorities. From these beginnings, over the last four decades the idea has blossomed, expanding both geographically and historically to encompass variegated environmental struggles worldwide, including those from centuries past. Why does this concept have such resonance and wherein lies its usefulness? This chapter examines these questions from the point of view of the Global South. I begin with some background on what is meant by the Global South and by environmental justice. I then use the customary four-pillar formulation of environmental justice – distributive justice, procedural justice, corrective justice, and social justice – to explain the different theoretical and practical ways in which this concept is helpful for understanding environmental struggles across the Global South.