In New York, the powerful figure of Robert Moses (1881-1981) knew how to take advantage of the opportunities that the development of transport technology offered towards the functioning of large cities. Moses was responsible for the construction of large communication infrastructures, large housing projects and public recreational facilities, such as parks and swimming pools, and pursued an aggressive urban renewal policy with the construction of new large-scale housing compounds in the depressed areas of the city.
With the Housing Act 1949, the State declared its intention to provide “a decent home and a pleasant environment for every American family”. The aims of the new housing policy was to eradicate slums and substandard housing, and promote community development and new development programs, encouraging the introduction of new sets of large-scale housing in rundown areas of New York but also in recoverable and consolidated neighborhoods.
From one of the New York City neighborhoods, Greenwich Village, emerged what Mel Scott defined as “popular howl”; that managed to recollect and convey the feelings of many people who disapproved of the brutal new development processes within the consolidated urban neighborhoods. The clearest manifestation was the publication of the book The Death and Life of Great American Cities in 1961. Peter Hall has remarked that this book is one of the most influential in the history of 20th-century urbanism (Hall, 1997). Written by Jane Butzer Jacobs (Scranton, Pennsylvania, 1016-Toronto, 2006) in a brisk language more proper of journalism, in which she had initiated herself in writing, it gives the point of view of someone who has based her story upon her own personal experience.
Jacobs inherited her vital attitude from her father, whom she described as “intellectually very curious, bright and independent. In some ways he was like a detective.” Thanks to him, she and her siblings perceived their surrounding reality as a “mosaic of stories.”  A romance with the architect Robert Jacobs gave her the family stability necessary for New York and later for Toronto, where they fled on account of the Vietnam War.
She attended the first Urban Design Conference held at Harvard University in 1956 and her communication was The Death and Life of Great American Cities. Josep Lluis Sert, dean of Harvard’s Graduate School of Design since 1953, claimed that urban design becomes a new field of knowledge, based on the responsibilities of architects, landscape architects and city planners. Urban design should be a synthesis of these three professional fields. Lewis Mumford, Edmund Bacon and a representing of Team 10 were attendees of the conference, among others. This was a professional environment where professionals used very similar language, so the presence of Jacobs, in the words of Mumford “was like a breath of fresh air”.
Jacobs focused her vision of the street as a meeting place for the construction of the city upon a social basis conceived as the sum of different individual experiences, supported by personal interaction and bound to a specific location, which would give it its own identity. In the words of Eugene Birch, “it defined the essence of life in the city as a human interaction in the random, haphazard physically but socially viable small-scale heterogeneous neighborhood.” The expulsion of the population settled in neighborhoods went from being considered a mere consequence derived from the solution of the larger problem, i.e., that of housing, to a social drama that turned into a Gordian knot of the problems suffered by the city.
Mumford was amazed by the Jacobs’ observation ability, which was not limited to the perceptual appearance but to reaching to the emotional aspect, he agreed with his way of approaching the urban reality. Jacobs explained in simple language how many planners and management were indifferent to the fact that “a neighborhood is not just a set of buildings, but a social network of relationships and a haven of warm personal feelings associated with familiar faces such as a doctor, a priest or a butcher. No less than the idea of home they were holding in common the fact that Mumford was one of the most persistent critics of the work of Robert Moses in New York:
“Ever since 1949, when the national Housing Act was passed, the cities of this country have been assaulted by a series of vast federally aided building operations. These large-scale operations have brought only small-scale benefits to our city. The people who gain by the government’s handouts are not the displaced slum dwellers but the new investors and occupants.” 
The editor of Fortune magazine since the mid-forties, the urbanologist, Hollyngsworth William Whyte (1917-1999), had in mind publishing a collection of essays written by people who enjoy and live in the city from the point of view of the citizen, not from professional planners, politicians or businessmen who were in town for the purpose of its scope profession. Whyte, was a bestselling author whose prestige had been given for his work The Organisation Man, published in 1956. This book was a fierce critique of American conformist attitude.
In 1958, Fortune featured an essay to participate in a publication on urban centers, object of interest since the birth of urban renewal which peaked after World War II. Whyte had read the Jane Jacobs communication at Harvard and offered to include it in the collection. Jacobs published the article titled “Downtown Is for the People” , where she wrote: “If tomorrow’s downtown is similar to most of the redevelopment projects foreseen for today, it will end up being a monumental hole. But the downtown could be habitable and exciting, and it is not too difficult to figure out how.” 
In 1958 an Urban Design Rockefeller grant allowed Jacobs to develop research work based on her article. Random House published the research as The Death and Life of Great American Cities, title of the Harvard conference in 1961. The success of her book was due to a large extent to the precise time in which her message was delivered, when urban renewal experiences were failing, as was its catalyzing-value, along with other social tendencies of the civic movement, that were demanding an active role in the issues of the city, confronting the obsolete official mechanisms of production and management.
The Death and Life of Great American Cities is a plea for hope in a resurrectional sense: Life after Death. The book was dedicated to the city of New York and her family. New York was definitely a unique city and the family was a social structure, an order within chaos. This is the tone in which the work is based on. Another significant aspect is the absence of illustrations in the text. This absence is justified on the grounds of interaction, because the reader will be able to insert the perceptual images that evoke the text choosing among those forming the visual archive of personal experience.
“Mother’s Jacobs home remedies” , Lewis Mumford article from the “Sky Line” column he wrote for the magazine The New Yorker, is one of the most interesting critics to the book. It is curious how Mumford resorted to female stereotypes, the housewife and mother. The mother Jacobs, is an allusion to the lack of professional training of Jacobs and the mistake about the scale of the city problem. Sarcastic is a caricature showing the article in which a lady opens the door to a woman, Jacobs, wrapped in fur above a gentleman with a pipe and hat, her husband, and says, “So this is the woman behind the man!”
The horrified attitude that Jacobs illustrated with bulldozers razing neighborhoods in the city, for Mumford is the same as she applied when she demolished all urban renewal efforts that had been developing in the professional planning. There was not a hint of critical content in Jacobs exposure to all these works, with errors in their results, but also successes that were worth being considered. Having agreed that the scale of interventions should begin in the neighborhood, they had to reach the region. He criticizes the overly simplistic attitude Jacobs has to understand that the only purpose of urbanism is to provide security to the streets, which would greatly reduce urban problems.
For Francoise Choay, the figure of Jane Jacobs remains concisely defined in her brilliant and emotional praise of the street of the big city, and more specifically, of the sidewalk. Her critique was valid and effective, but few were the Americans that could afford to live in neighborhoods such as hers.
Considering social activism to be a vital necessity, Jane Jacobs led the civil protests against Moses’ Lower Manhattan Expressway, lomEx, project, which included the layout of a highway running through Greenwich Village. The media transmitted it as a battle of David against Goliath. The project by Moses, presented in 1962, was born wrapped in controversy, but was not a new one. In the 20s, Nelson P. Lewis proposed an elevated cross-way connection on Canal Street between Holland Tunnel and the Manhattan Bridge, providing a direct link between New Jersey and Brooklyn. The LOMEX project was finally removed in 1968. David had won.
In either case, the legend of Jane Jacobs in the urban studies on gentrification keeps gaining strength. Texts such as this, result of a child murder, reaffirm the figure:
“Forty five hundred people live in the nine brick towers that make up the Grant Houses. The Manhattanville Houses, with six buildings are the home of three thousand people. (…) The projects are more than fifty years old and in severe disrepair. (…) Most of the city’s three hundred and twenty-eight housing projects are in poor condition. (…) For decades, the Grant and Manhattanville Houses had been embroiled in a feud. As in other projects, some young people joined “crews.” The Grant crew called itself 3 Staccs; Manhattanville’s was the Make It Happen Boys. The crews were not affiliated with established gangs, like the Bloods or the Crips, and their disputes were not about drugs or money. Rather, they fought over turf and status. Often, the conflicts seemed to be fuelled by little more than boredom.”  […]
El texto completo fue publicado en URBS 7(1)
 Wachtel, Eleanor (2003). Conversations with CBC’s Eleanor Wachtel. Toronto: Harper Collins.
 Mumford, Lewis (1962). Mother Jacobs’ Home Remedies. The New Yorker, 1, 148.
 The collection of texts is called The Exploding Metropolis (Doubleday, 1958) and featured William H. Whyte, Jane Jacobs, Francis Bello, Seymour Freedgood, and Daniel Seligman.
 Jacobs, Jane (1958). Downtown is for People. Fortune Classic, April.
 Mumford, Lewis, Mother’s Jacobs home remedies (1962). The New Yorker, December, 148.
 Gonnerman, J. (2005). A daughter’s death. New Yorker, October, 52-63