The second incarnation of the Project Global triptych investigates the water cycle—relevant as both input and output for the metropolitan metabolism. The thematic spans in terms of scale and lens: from geopolitical aspects to the individual human body, seeking to explore water as a crucial factor in the design of the built environment. Vienna served as an exemplar of a modern planned metropolis, related to water infrastructure and regulations. Mexico City, a city flooding and at the same time running out of water, formed the ground for interrogation.