This chapter provides an overview of the background, key drivers, and impacts of climate change and urbanization. It reviews the major contributors to global warming, focusing on greenhouse gas emissions from energy production, industrial processes, deforestation, transportation, and food systems. The wide-ranging effects of climate change on ecosystems, human health, water availability, and economic development are discussed in the context of global environmental change, with particular attention to issues of environmental justice. It also introduces the urbanization process, including shifts in population structure, increased rural-to-urban migration, and processes of industrialization and globalization, and outlines related environmental impacts, such as elevated surface temperatures, pollution, and ecosystem degradation. It highlights the combined challenges that climate change and urbanization pose for sustainable and resilient urban development. The relevance of international frameworks such as the Sustainable Development Goals is emphasized in guiding urban responses. Finally, this chapter summarizes major global and national adaptation targets and identifies common barriers to climate action, including limited public awareness, institutional constraints, and financial challenges. This chapter provides essential background for interpreting the urban surface thermal environment as a key manifestation of the combined effects of climate change and urbanization.