Green belt development represents a strategic approach to sustainable urban planning and climate resilience. As multifunctional landscapes comprising agricultural lands, forests, parks, and open spaces that encircle urban areas, green belts act as ecological buffers, mitigating urban sprawl, enhancing biodiversity, and safeguarding critical ecosystem services. They significantly contribute to carbon neutrality by sequestering atmospheric CO₂, regulating microclimates, and mitigating the urban heat island effect. Moreover, green belts improve air and water quality, support groundwater recharge, and offer natural defences against environmental hazards such as floods and wildfires. Socioeconomically, green belts preserve the cultural and historical identity of peri-urban regions, promote recreational opportunities, and stimulate sustainable land use through urban regeneration and brownfield redevelopment. Despite policy and implementation challenges, green belt development remains a vital land-use strategy to balance urban expansion with environmental conservation. This chapter underscores the role of green belts in fostering low-carbon, livable cities and highlights their potential as a cornerstone in achieving global sustainability and climate mitigation targets.