Design is people.

The more successfully a city mingles everyday diversity of uses and users in its everyday streets, the more successfully, casually (and economically) its people thereby enliven and support well-located parks that can thus give back grace and delight to their neighborhoods instead of vacuity.

A city street equipped to handle strangers, and to make a safety asset, in itself, our of the presence of strangers, as the streets of successful city neighborhoods always do, must have three main qualities:

First, there must be a clear demarcation between what is public space and what is private space. Public and private spaces cannot ooze into each other as they do typically in suburban settings or in projects.

Second, there must be eyes upon the street, eyes belonging to those we might call the natural proprietors of the street. The buildings on a street equipped to handle strangers and to insure the safety of both residents and strangers, must be oriented to the street. They cannot turn their backs or blank sides on it and leave it blind.

And third, the sidewalk must have users on it fairly continuously, both to add to the number of effective eyes on the street and to induce the people in buildings along the street to watch the sidewalks in sufficient numbers. Nobody enjoys sitting on a stoop or looking out a window at an empty street. Almost nobody does such a thing. Large numbers of people entertain themselves, off and on, by watching street activity.

[Public housing projects] are not lacking in natural leaders,' [Ellen Lurie, a social worker in East Harlem] says. 'They contain people with real ability, wonderful people many of them, but the typical sequence is that in the course of organization leaders have found each other, gotten all involved in each others' social lives, and have ended up talking to nobody but each other. They have not found their followers. Everything tends to degenerate into ineffective cliques, as a natural course. There is no normal public life. Just the mechanics of people learning what s going on is so difficult. It all makes the simplest social gain extra hard for these people.

As children get older, this incidental outdoor activity--say, while waiting to be called to eat--becomes less bumptious, physically and entails more loitering with others, sizing people up, flirting, talking, pushing, shoving and horseplay. Adolescents are always being criticized for this kind of loitering, but they can hardly grow up without it. The trouble comes when it is done not within society, but as a form of outlaw life.

The requisite for any of these varieties of incidental play is not pretentious equipment of any sort, but rather space at an immediately convenient and interesting place. The play gets crowded out if sidewalks are too narrow relative to the total demands put on them. It is especially crowded out if the sidewalks also lack minor irregularities in building line. An immense amount of both loitering and play goes on in shallow sidewalk niches out of the line of moving pedestrian feet.

You can't rely on bringing people downtown; you have to put them there, ... The Death and Life of Great American Cities.