This book offers an in-depth exploration of the ergonomics of the built environment as a holistic, user-centered, and practice-oriented discipline that integrates human factors into architectural and urban design. It examines how the physical, cognitive, and organizational dimensions of human behavior shape spaces that foster comfort, efficiency, and well-being. Introducing the core theoretical foundations of ergonomics and human factors, the book underscores the importance of user participation, diversity, and adherence to design standards as essential components of effective spatial design. It proposes a systematic approach that translates these principles into an iterative design process, illustrated through practical examples across diverse architectural and urban contexts. Building on this foundation, the text presents validated qualitative tools and methods for assessing how built environments influence human performance and well-being. The role of ergonomics in sustainable and green building design is discussed throughout, including its contribution to maintenance practices that enhance socio-technical efficiency, safety, and environmental responsibility. Concluding with reflections on global sustainability challenges, the book positions ergonomic design of the built environment as a crucial framework for advancing human health, well-being, and resilience in contemporary urban life.