N.J. Habraken 
Appearance of the Form [PDF ebook] 
Four Essays on the Position Designing takes between People and Things

Originally published in 1985 this book explores, in four interwoven essays, the many ways human life and built form interact and the place that professional designing takes in this interaction. Together, the essays touch on a number of ideas: the idea that our position in space relative to the thing we are designing determines the methods we apply when designing it; the idea that designing is about making proposals, and is therefore a social act first of all; and the idea that agreements, consensus and above all conventions shape the act of designing things independent of their creative qualities.