This chapter critically examines environmental degradation in the global peripheries, specifically Africa, Southeast Asia, and Latin America, through the lens of world-systems theory and ecological inequality. It argues that environmental harm in these regions is neither incidental nor isolated but rather structurally embedded in the political economy of global capitalism, where core economies externalize ecological costs to sustain commodity and capital flows. Drawing on interdisciplinary evidence, the chapter explores how deforestation, industrial pollution, biodiversity loss, and climate change converge in extractive frontiers shaped by colonial legacies, neoliberal economic orders, and multinational corporate strategies. Comparative case studies from the Congo Basin, Amazon Basin, and Southeast Asia illustrate how ecological degradation intertwines with land dispossession, livelihood disruptions, and cultural erosion, disproportionately affecting indigenous and marginalized communities. The chapter also highlights spaces of resistance, where grassroots movements, indigenous activism, and alternative ecologies, such as agroecology and eco-tourism, challenge extractivist paradigms and reimagine development pathways. By linking ecological justice, indigenous sovereignty, and transnational accountability, the analysis calls for a radical rethinking of global environmental governance. It argues for systemic transformation that dismantles the unequal ecological exchange between the core and the periphery, embeds environmental justice in trade and climate policies, and centers local knowledge in sustainability transitions. The chapter attempts to reframe peripheral ecologies as not merely victims of exploitation but as crucial sites of resistance, innovation, and ecological renewal within an interconnected world facing unprecedented environmental crises.