The concepts of green buildings and sustainable cities emerged globally during the 1970s environmental movement, sparked by the 1973 oil crisis and a growing awareness of resource depletion and ecological damage. These terminologies were formally introduced to bridge the gap between rapid urban development and environmental preservation, providing a standardised framework to combat climate change, reduce massive energy consumption, and curb carbon emissions. While ‘green building’ focuses on the micro-level utilising eco-friendly materials, water conservation, and energy efficiency within individual structures ‘sustainable cities’ scales these ideas to the macro-level, integrating green infrastructure, public transit, and waste management into a cohesive urban ecosystem. Together, these terms provide architects, urban planners, and governments with a shared vocabulary and actionable goals to create resilient human habitats that balance economic growth with planet preservation. Green buildings and sustainable cities are deeply connected in Oman's urban planning, acting as the fundamental building blocks for the nation's eco-friendly future. As urban population grows, the Sultanate faces rising energy demands, water scarcity, and high temperatures. To address these challenges, Oman is integrating green building practices into its broader urban strategies to create resilient, low-carbon cities. Oman Vision 2040 serves as the national roadmap for sustainable development. A major pillar of this vision is the creation of sustainable, smart cities that protect natural resources and mitigate the impacts of climate change. Individual green buildings are the structural units that make this vision possible. A city cannot achieve true sustainability if its individual structures consume excessive energy and water. By adopting green building standards, Oman ensures that new urban developments actively contribute to national environmental targets. In Oman's desert climate, buildings traditionally consume massive amounts of electricity for air conditioning. Green buildings break this cycle through passive design strategies. They utilise high-performance thermal insulation, double-glazed windows, and smart orientation