HOPING SOMEDAY to visit downtown Paris? Or hang out at the heart of the action in Tokyo or Rome? You might want to rethink your plans because those sights don?t exist. In fact, many great cities around the world lack the one distinct center we expect to find in North American metropolises. In London, for instance, you typically go to Kensington for fashionable shopping, Leiceister Square for movies, the South Bank for trendy nightlife, the City district for business dealings, and a whole host of outlying enclaves for hip or ethnic attractions.

And now, as many American towns proudly showcase their booming downtowns while others work hard to reinvigorate theirs, a group of planners suggest that urban vitality may depend on having multiple centers within each city. A major conference focusing on redeveloping New York after 9/11, ?1=5,? sponsored by the Center for Architecture in New York, explored the small-is-beautiful idea of spreading new development throughout the city?s five boroughs.

?What if, instead of fighting the displacement of jobs and housing from lower Manhattan, we harnessed it to shape the best possible growth in other quarters,? asked the design magazine Metropolis (Aug./ Sept. 2002), summarizing discussion at the conference. ?And what if multi-centered urbanism was important not only as an idea for rebuilding New York but as a blueprint for good planning practice in many cities for decades to come??

These urban theorists weave an image of vibrant urban tapestries where you find some combination of offices, housing, shops, theaters, restaurants, music clubs, museums, and public plazas clustered together amid bustling street life at a number of spots around town. The planners are quick to point out that what they envision is something different from the decentralized sprawl that characterizes most development today. These lively business districts would resemble traditional downtowns more than the strip malls and power centers that dot suburbia. It would be like having a number of Harvard Squares or Dupont Circles in addition to downtown Boston or Washington. With an emphasis on pedestrian-friendly environments and transit connections, these new smaller town centers could ease the traffic congestion, high rents, and unattractively huge scale of many downtown districts. It might be like having a little bit of Paris in your own backyard.