Chapter 1: Background and definition of sustainability

Chapter 1 explores the evolution of sustainability within the built environment, tracing its conceptual origins from early environmental awareness to global frameworks like Agenda 21 and the UN Sustainable Development Goals. It defines key principles including climate mitigation and adaptation, planetary boundaries, the triple bottom line, and the Five Capitals. The chapter highlights the emergence of sustainability rating systems, frameworks, and the circular economy, emphasising the built environment's role in addressing climate and social challenges. It concludes by examining urban development ecosystems, nature networks, mobility, and enabling systems, framing sustainability as a dynamic, multi-scalar process essential for future resilience.