Histories of colonial expropriation and the nature of political and economic systems shape environmental justice struggles. However, inequality and capitalism are institutionalized very differently in different contexts and counties. This chapter advances scholarship on a comparative politics of environmental justice in diverse contexts. It draws on the tools and concepts from institutional analysis and comparative environmental politics to investigate the structuring effects of institutions while also accounting for the differences of political capabilities of main actors in society, market, and politics. The political economy of policies and institutions (PEPI) framework developed in this chapter facilitates a theoretically grounded investigation into how the key features social, economic, and political contexts, in conjunction with legal and institutional architectures, shape environmental justice advocacy, policies, programs, and outcomes. The PEPI framework makes visible the remarkably different trajectories of environmental justice movements and the political and policy interventions needed to realize the goals of environmental and climate justice in diverse contexts.