Sustainability and Cities examines the urban aspect of sustainability issues, arguing that cities are a necessary focus for that global agenda. The authors make the case that the essential character of a city's land use results from how it manages its transportation, and that only by reducing our automobile dependence will we be able to successfully accomodate all elements of the sustainability agenda.

The book begins with chapters that set forth the notion of sustainability and how it applies to cities and automobile dependence. The authors consider the changing urban economy in the information age, and describe the extent of automobile dependence worldwide. They provide an updated survey of global cities that examines a range of sustainability factors and indicators, and, using a series of case studies, demonstrate how cities around the world are overcoming the problem of automobile dependence. They also examine the connections among transporation and other issues-including water use and cycling, waste management, greening the urban landscape, and more-and explain how all elements of sustainability can be managed simultaneously.

The authors end with a consideration of how professional planners can promote the sustainability agenda, and the ethical base needed to ensure that this critical set of issues is taken seriously in the world's cities.

Newman and Kenworthy argue that the car, unlike public transport, offered people who could afford it freedom to live anywhere in a city and get quickly to any other part of it. It appeared to remove the need to plan land-use. Anything could be built anywhere with drivers determining their own routes to and from home to work, shops, schools and entertainment. In the "car-city" - which Newman and Kenworthy distinguish from the "pedestrian city" and the "transit city" - it is possible to develop in any direction and not just along rivers, tramlines or railways. Dispersed low density housing becomes accessible and popular. Town planners can separate residential from industrial zones accelerating decentralisation. Public and commercial buildings no longer need to cluster as a product of the convergence of private and public investment in a particular place. Public transport constricted by timetables and fixed routes becomes second class travel.

Where the car city has been taken to extremes as in Newman and Kenworthy's intellectual territory - America and Australia - the penny dropped soonest. The social consequences that attended driving people off streets and creating boundaries round parks, squares, promenades, pavements - which had served as milieu for human interaction - only began to be widely accepted quite recently. Only now is a wedge of new economic logic being driven between the car and its enduring connection with the good life.

The car, once it ceased to be an indulgence of the rich, always represented a balance between liberation and dependency. Today, the choices promised by cars are linked transparently to those they take away. Everyone knows about exhaust emissions and most drivers, outside of advertisements, experience worsening road conditions. There is growing despondency among those who would like to use their cars less. They realise alternatives won't work unless people switch in large numbers to other ways of getting around. But the public space needed to take to the streets to walk or cycle and take trains and buses is unavailable. Many see public space as hazardous for themselves, and perilous for their children. Deprivations long imposed on people without cars apply, with increasing force, to people with them. New technology may reduce vehicle emissions. It cannot recover the enormous interaction space taken out of circulation by road traffic. Before that lost social space can become available for people outside cars, a legal and moral space has to be reclaimed.

This is why the idea of sustainability is slowly and surely turning into a value. It is the big idea which legitimates unpopular regulation. It offers space for the entrepreneurs of the future, exciting third world policy makers who want to leap a stage in the industrial revolutions of the richer nations. It is the idea around which people are ready to form alliances that go beyond their interests; a concept which "did not come so much from academic discussion as from a global political process." Newman and Kenworthy speak of their book being "many years in preparation", a book that is a "combination of text book and life story" deriving from work with city governments and voluntary groups attempting to address a major global and local issue of how people "can simultaneously reduce their impact on earth while improving their quality of life".

This books aims to show how a city's use of land determines and is determined by its dominant forms of transport. It describes how policies aimed at creating sustainable relationships between humans and their environment necessarily revolve around a city's land-use-transport formula. Getting this right is a prerequisite for urban renaissance.

What makes this book of especial value and its focus provocative is that so many cities and towns are now "auto-dependent". Because cars are sold on the basis of the freedoms they offer, policies to regulate so dominant a form of transport, even when those freedoms are nurtured in the imagination rather than available in the material world, arouse strong protest. Attempts to diversify people's transport choices are regularly characterised as restrictive and even oppressive. Instead of being seen as a catalyst for wealth production, governments addressing challenges to the reputation and wealth of cities caused by "auto-dependence" are seen as depriving large numbers of citizens of fundamental freedoms. The "motorist" has become a late 20th century everyman, affected from all angles by policies to restore a balance in cities between space allocated to rapid movement and space where citizens can engage in civil exchange.