Since its formal foundation sixty years ago the discipline of urban design has chiefly concerned itself with a response to the Modernist approach to city building. Modernism held up the idea of a city composed of buildings that were free-standing, internally-focused, unadorned, efficient solutions to the needs of humans for shelter and privacy. These buildings were big, as made possible by new construction methods. They were constructed and designed as singular objects, meaning that they did not combine with nearby buildings or open space to create a coherent form. The only coherent form was the building itself. The new role played by the building in the city caused a fundamental reordering of the shape of cities. And, in this instance, function followed form.
The new shape of the city altered how people lived and moved about, what kind of places they spent time and how the interacted socially. Throughout human history cities were formed of a dense built mass, cut through with narrow alleys, squares, and a few broader thoroughfares. These openings in the built form provided a space for the public life of the city in addition to circulation and access to buildings. The public realm was shaped by the many buildings which surrounded it and life that flowing through it into and out of these buildings. It was composed of nothing more than the sum of the relationships between these elements (Kostof 1991).
The modernist approach to architecture and city building was an acknowledgment of the 20th century changes in construction and transportation technology and it was an earnest attempt to deal with the many problems of the industrial city, with its crowded, polluted, and unhealthy slums, economic inequality, and congested streets. Still, urban designers found it necessary to repudiate many of the tenets of the modern city and its effects in their own work. This was perhaps most powerfully achieved by Jane Jacobs in her book The Death and Life of Great American Cities, in which she the compares modernist city planning to the archaic medical practice of bloodletting, saying “years of learning and a plethora of subtle and complicated dogma have arisen on a foundation of nonsense.” Jacobs calls out for a new discipline of city planning based around the ways cities work in reality, derived from nothing more than the observation of cities themselves (J. Jacobs 1961).
The key element that Jacobs searches for in her study of the real functioning city is life, and the circumstances and environments which sustain it in an urban environment. This life is found in the street, in the “sidewalk ballet”, in well-used parks and in safe, supportive, vibrant neighborhoods. This quality has been sought by many theorists of urban design throughout the development of the field. It is something like “magic”, a “sense of place”, greatness, life, and it happened in the public realm, a result of the complex interplay of the built elements of the city and of lives of the people who inhabited them. This quality was perhaps best characterized by Jan Gehl, who called it the “life between buildings” (J. Jacobs 1961) (A. Jacobs 1993) (Cullen 1961) (Gehl 1987).