Trying to describe the general flavour of the rich feast of theories and models presented in this book, I have three separate but related impressions. The first is how little we have addressed the specific remit, to discuss the impact of technological change upon urban form; of technological change itself we read much, of urban form relatively little. The second is that the chapters really address the situation only in the advanced industrial countries, and a relatively narrow group of advanced countries at that. The third is the overwhelming impression of pessimism, of passivity in the face of rapid technological, economic and social change. I should like briefly to ask why our contributions are like this, and what if anything we could do in further work to reduce or remove these limitations.