The theory of architecture implicit in our world today, Christopher Alexander believes, is bankrupt. More and more people are aware that something is deeply wrong. Yet the power of present-day ideas is so great that many feel uncomfortable, even afraid, to say openly that they dislike what is happening, because they are afraid to seem foolish, afraid perhaps that they will be laughed at. Now, at last, here is a coherent theory which describes in modern terms an architecture as ancient as human society itself.