Why discuss sustainable construction in such abstract terms as the ‘bioeconomy of buildings’? This introductory chapter focuses on three main reasons for doing so. The first is the specific emphasis on energy within the tradition of bioeconomic thought. The second reason is the potential to bring a historical and intercultural perspective into focus. Within the framework of bioeconomy, reflecting on (past) agrarian bioeconomies becomes relevant, especially in terms of land allocation and its uses for food, fiber, fuel, and feed over time. Historical examples can serve as ‘distant mirrors’ helping to reflect on present techno-economic approaches. By contrast, the focus on sustainability is often tied to short-term, entirely quantifiable goals, particularly those needed for certification. Finally, the third reason for discussing a bioeconomy of buildings relates to the term itself, which is sometimes used as an intriguing metaphor: bio suggests life, connecting to a cultural dimension of sustainability. By examining the lifecycle and beyond of materials, and the cultural meanings embedded in architectural practices, we can rethink buildings as part of a broader ecological system, where resources are circulated and environmental impact is reduced.