The author's central argument is that built environment is universally organized by the Orders of Form, Place and Understanding. These three fundamental, interwoven principles correspond roughly to physical, biological and social domains. Historically "ordinary" environment was the background against which architects built the "extraordinary". Drawing upon examples from archaeological and contemporary sites worldwide, the author illustrates recent shifts in teh structure of everyday environment. One effect of these tranformations, Habraken argues enabled architects to formally enhance and innovate while still maintaining environmental conherence. Consequently architects must now undertake a study of the ordinary as the fertile common ground in which form- and place-making are rooted. In focusing on built environment as an autonomous entity distinct from the societies and natural environments that jointly create it, this book lays the foundation for a dialogue on methodology and pedagogy, in support of a more informed approach to professional intervention.