New York has long lagged behind such cities as Paris, London, and Tokyo in its reputation for cutting edge architecture. Recently, though, it has had its internationally recognized triumphs, such as Yashio Taniguchi’s expansion of the Museum of Modern

Art and Richard Meier’s shiny new condominiums in Chelsea. While private developers and wealthy cultural institutions are busy molding the city’s skyline, the Department of City Planning has begun helping to bring some of that high design to the streets below.

As part of an initiative to step up the quality of urban design, the city agency is hiring high-profile, trend-savvy architects who are in effect acting as urban planners, in the first widespread planning effort since the 1960s that includes a comprehensive rezoning effort, several large-scale building projects, and architectural competitions.

“We are not just rezoning but trying to think comprehensively about how to preserve affordability, street vitality, and open public spaces,” the director of the department, Amanda Burden, said. The idea, she said, is to be proactive and think intelligently about urban growth. By offering well-articulated master plans, the city hopes to give developers blueprints to build upon.

While architects have been involved for decades in city planning initiatives, not since the 1960s has the city taken such bold steps or given so much prominence to progressive architectural ideas in the realm of city planning, architecture experts say.

“Before, it was always the firms that did business as usual that got all the planning commissions,” a partner at SHoP/Sharples Holden Pasquarelli, Gregg Pasquarelli, said. “Now there is a clear indication that ‘business as usual’ is not enough for a city as important as New York.”

The city, under the direction of Ms. Burden, is both raising the bar on New York’s design expectations and attracting attention through its use of design competitions, a method long favored by many cities in Europe. Architects who have excelled on the international scene are winning some of New York City’s most coveted planning projects.

“If you had told me in January 2001 that Libeskind would be doing a major master plan in Lower Manhattan, I would have said you are crazy,” a senior editor at Architectural Record magazine, Clifford Pearson, said, speaking of Daniel Libeskind, who created a master plan for ground zero. “But a lot has changed since then.”

Mr. Libeskind’s plan may be New York’s most prominent, but more than a dozen other large-scale planning projects are on the drafting boards for sites in all the boroughs.

A leading British architectural firm, Richard Rogers Partners, along with a seven-year-old design firm, ShoP/Sharples Holden Pasquarelli, is working on a master plan for a stretch of the East River waterfront. The plan, which curves around the tip of Manhattan from Battery Park City to the East River Park, is intended to open public access to the waterfront for much of the Financial District by building a series of parks and recreational spaces, as well as a two-mile esplanade.

On the West Side, a New York-based architectural firm, Diller, Scofidio+Renfro, has teamed up with Field Operations to redesign the High Line, 1.45 miles of elevated railroad track meandering through Chelsea. In the 1990s, Diller Scofidio won the praise of critics with such high-tech design installations as a manmade “cloud” on a lake in Switzerland. The two architectural firms plan to transform the abandoned High Line into a series of gardens and public spaces linked by a walkway more than two stories up, offering views of the neighborhoods below.

Diller, Scofidio+Renfro is also working on a master plan for Lincoln Center, which will mold the concrete corridor on 65th Street between Amsterdam Avenue and Broadway into a main campus thoroughfare.

“It’s a hot scene in New York now,” the director and founder of Field Operations, James Corner, said. “Ten or 15 years ago, architects would have to go to Paris or London to make names for themselves, even architects based in New York.”

Meanwhile, Field Operations is turning a garbage dump into a cluster of parks and sports fields, and a patchwork of swamps and wetlands into a cohesive landscape. The 2,200-acre redevelopment of Fresh Kills, the city landfill on Staten Island, is scheduled to begin as early as 2007.

Perhaps the most provocative project is Thom Mayne’s design of the Olympic Village in Long Island City. Whether or not the city wins its bid for the 2012 Olympics, Queens will still get a new master plan from Mr. Mayne, whose buildings are known for their angular forms. His East River design will include 4,600 units of new housing, including a serpent-like structure along the riverfront.

“It is not just about a business model anymore,” Mr. Mayne, of Santa Monica, Calif.-based Morphosis, told The New York Sun. “Rather, these projects are about balancing human needs with economic concerns at a large scale.”

Historically, the city’s planning department has been more focused on reviewing development bids than molding them. That began to change when the fabled planning tsar Robert Moses started to make sweeping changes to the city.

In the 1950s and 1960s era of urban renewal – now considered by many planners and architects to be a disaster – entire neighborhoods, such as Downtown Brooklyn, were bulldozed to make room for boxy residential towers. For decades, the failures of urban renewal have haunted planning efforts throughout the city.

“In New York, there has been 30 years of paralysis in terms of planning,” Mr. Pasquarelli said, “and we are just starting to shake that hangover off, and it is time to think big again.”

Many architects attribute the renewed interest in planning and architecture to the widely publicized process of choosing a design for the master plan of ground zero, which drew the attention not only of architects but also of the public.

“There was this big meeting at the Javits Center, where architects like Beyer Blinder Belle presented their plans,” said Architectural Record’s Mr. Pearson.” And the people said, ‘No, this is not what we want.’ I think it initiated a conversation that is still going on and convinced developers in the city that design is something that can help sell their project.”

Rebuilding ground zero may have brought the issue into the public consciousness. But according to Ms. Burden, Mayor Bloomberg has long understood that it is not enough to promote development, the city needs to recognize that sophisticated design choices directly contribute to the public’s welfare.

“The bottom line is that great architects and great architecture translates into economic development,” Ms. Burden said. “It brings jobs, it brings investment, and raises the property value. And the mayor has always understood this and is making a push for the city to be more proactive in bring architectural excellence to New York.”

Architects are beginning to take notice.

“This administration, for the first time in a long time, has understood the bigger picture, that New York City is a world capital and therefore is worthy of the highest levels of design,” Mr. Pasquarelli said. “They see it doesn’t cost more money to have design excellence. It is just about making an effort to find the best people to think creatively to make a positive environment.”

As many large-scale planning projects await public review and approval, however, some planners are reluctant to declare success before seeing the final product.

“The question here is, architects spend all their time designing individual buildings, so when they are given the job of designing an area or a neighborhood, are those details and design schemes able to translate on such a large scale so they will fit in with the social fabric,” an urban planner and architect, Craig Whitaker, said.

For many critics, though, it is too soon to tell.

“I think the jury is still out,” Mr. Pearson said. “There haven’t been that many successful large-scale urban projects, but there is starting to be some.”