What will the healthy and sustainable city of the future look like? How do we design this city? What information and which methods do we need to tackle problems such as scarcity, inequality, and climate change? Tricky problems do not always call for far-fetched solutions, but they may require a change of perspective. This book advocates such a change of perspective in the study of the urban environment. It states that designers who wish to truly improve the functioning of cities and solve the urgent problems at hand, cannot afford to focus only on their spatial manifestation. Instead, they are encouraged to conduct thorough research into its underlying system: the operation, use and performance of the urban fabric. This research involves new, often digital, information streams and methodologies that help us understand the complex metabolism of our cities. Technology and digital innovation swiftly move forward. In a time when we ask more and more of our cities, the authors encourage us to embrace the knowledge, opportunities and typologies generated by this innovation.