This chapter examines climate change as one of the most critical global challenges, emphasizing its profound impacts on human welfare, economic systems, and environmental sustainability. It analyzes major international climate agreements—including the UNFCCC, the Montreal Protocol, the Kyoto Protocol, and the Paris Agreement —to evaluate their roles in shaping global climate governance. The findings show that the effectiveness of these frameworks varies considerably due to differences in legal enforceability, national commitments, and geopolitical constraints. The chapter highlights human activities, particularly fossil fuel combustion, as the primary drivers of global warming and discusses debates over responsibility between historically high-emitting advanced economies and rapidly growing emerging economies. The economic consequences of climate change are assessed through sectoral evidence on public health, agriculture, tourism, and energy infrastructure. Overall, the chapter underscores the need for robust economic models and inclusive governance structures that integrate climate mitigation with sustainable development to strengthen resilience under increasing climate uncertainty.