Everywhere, eyes are on the rebuilding of Ground Zero. Pascal Marigall, the former mayor of Barcelona, told a visiting group of activists and public officials not long ago,  "New York is the city of the world: not the capital but the city. What New York does concerns everyone. It is a reference point. What you do there will shape city building around the world."

Having attracted such attention, New York is certainly ready to shoulder its responsibilities. The city just completed the most publicized urban design competition ever to rebuild the site of the Twin Towers.

During very large public forums at the start of the process common themes emerged. New Yorkers said they wanted to honor the attack and the city's vibrancy with human scale and human interaction, rather than just architectural statements. They wanted a return to streets, the capillaries though which the real lifeblood of a city flows. They wanted designs that nurture vibrant urban life and reflect that we live in an environmentally different time, a time when it is possible to do things to improve, not degrade, the environment. In short, they wanted Smart Growth.

Libeskind's Inspired Design and Smart Growth
Seven teams competed and the winner was a set of crystal skyscrapers dominated by a 1,776-foot tower submitted by Daniel Libeskind, who is best known for his design of the Jewish Museum in Berlin.

Although the spotlight so far has been on the drama and the avant-gardism of Libeskind's faceted towers, the harder part that residents and officials are only starting to approach is also more fundamental: How to fit Libeskind's design into the urban fabric of lower Manhattan.

It is urbanism, after all, that is the defining characteristic that makes New York the greatest of all American cities. No other American city matches New York for the mostly seamless connection between streets, transit, buildings, neighborhoods, public spaces and, of course, its diverse economy and people. The city's success, before and after September 11, reflects the cultural and economic value that comes with adhering to the community-building principles of Smart Growth.

Old Trade Center Never Fit Well
Ironically, the World Trade Center was generally regarded here as the antithesis of Smart Growth. It not only replaced a vibrant mix of economic uses and historic streets, it severed a piece of the city from its intricate web of streets. The Towers never functioned well urbanistically, with their second-story, windswept plaza and total disconnect from adjacent streets. And it took decades for the Towers to succeed economically. For years, government filled most offices because the market could not absorb the excessive space.

After September 11, new public assessments about how the 16-acre Twin Towers site should be used led to constructive discussion about urbanism. What is it? How does it evolve? What creates lively street life? How do pedestrians earn priority over cars? And how does New York more effectively integrate mass transit systems into the area?

These are some of the very same questions being asked in dozens of other metropolitan regions as the nation's cities reconsider how to again establish the vibrancy needed to attract more people to live and work in an urban setting. Those discussions could well be informed by what's going on the Twin Towers site, which has come to be regarded as both hallowed ground and the  hopeful start to a new era for urban America.

A Mall, Transit, and City Streets Restored
It certainly is not easy. The operator of the original Twin Towers underground mall is still expecting to include an indoor mall on the rebuilt site. The amount of retail space has been quietly increased in size from 450,000 square feet - about twice the size of a Wal-Mart - to one million square feet. Westfield, the operator of the retail spaces, is a suburban mall developer that only knows the enclosed model. But street entrances for retail stores are essential for human vibrancy. An enclosed mall is antithetical to urban districts where street life is a top priority.

Appropriately, transit access is a priority. A smooth weaving of existing transit lines would be a marked improvement for lower Manhattan. City residents -- not suburban commuters -- must have priority. Transit should make it easier to work and reside in the city rather than to facilitate life outside of it. Inappropriately, some officials are willing to sacrifice local subway service to improve suburban access and convenience.

On the positive side, Libeskind's plan provides generously for reconstructing some of the city streets wiped out when the Twin Towers were built in the 1960s. Well-designed streets are the essential enablers of good urbanism.  Multiple streets also allow for a variety of small public spaces. Public spaces cannot exist in private buildings.

Time also is a friend. New York's Republican Governor George E. Pataki proposed a plan last month that calls for completing new transit stations and Mr. Libeskind's crystal towers by the end of the decade. This provides citizens and Smart Growth advocates time to recognize and solve the community-oriented design flaws.

The Twin Towers were an icon appreciated most from afar, a powerful symbol of bigness beyond need, size for its own sake. We need symbols as much as ever, but new symbols reflecting human and urban values of a different kind.

Roberta Brandes Gratz, an international lecturer on urban development issues and a former reporter for the New York Post, is the author of "The Living City: Thinking Small in a Big Way," and "Cities Back from the Edge: New Life for Downtown." She lives in New York City and can be reached at LIVINGCITY@aol.com.