If you ask a child to draw a picture of a house he will draw the same shape no matter what sort of dwelling he lives in, the pictogram will be of a square building with a pitched roof, sometimes with a chimney and a curl of smoke ascending to a sky with a smiling sun. That is “house” and I believe that the farther the designer strays from that subconscious prototype the less it becomes house. On that premise I designed a series of prototypical houses. These were specifically houses that could be built inexpensively, based on a 20 foot by 40 plan, a dimension we had discovered was practical in terms of building. In America all building materials come in units of four feet, divisions or multiples of that dimension, so using that module automatically induced a cost savings. I had also discovered that dimension gave room sizes that were usable and practical. To that I added a 45º pitched roof, a diagonal cut of a piece of plywood with no waste, again a practical and cost saving gesture. I discovered that the possibilities within this formal envelope were nearly infinite. Like the structure of a sonnet or a fugue this order provoked innovation rather than inhibiting it. So a collection of these explorations took shape. At that time my friends Massimo and Lella Vignelli came to visit me. Always my most trusted critics and mentors I showed them the collection of designs. Massimo became very excited about them and immediately seized upon the accessibility of the design to a user. He christened them “Friendly Houses” and proposed a portfolio of the designs and, being Massimo Vignelli, he immediately designed the book.