The urban environment of cities plays a major role in shaping the way we live and work. In a highly urbanized world, the urban environment has become a fundamental component to how we use our resources, how we develop our economies, and how we interface with the local and global natural environments. The complex urban systems of global cities play a major role in that. Buildings, for example, determine how much energy and water we use to maintain thermal comfort and wellbeing, while transportation systems regulate the energy required for mobility and how much pollution is emitted in the process. Despite the apparent state of flux in cities, most components of the urban environment have a particularly long lifespan. A road network for example, can last for decades if not centuries, while buildings can have a lifespan of over 50 years. This means that decisions taken in the planning of cities as well as the design of buildings and urban systems continue to shape the sustainability of our cities for decades after they had been taken. It also suggests that if the designed urban environment lacked sustainability, the associated economic development and resource consumption levels can remain locked-in for decades until their urban foundations are addressed. In this context, urban sustainability can be defined as a city�s ability through its location, climate, size, density, and the organization of its urban systems and urban assets, to reduce its overall environmental footprint and its dependence on resources from its surrounding hinterland.