Morgan Stanley, the largest securities company in Manhattan, announced an agreement yesterday to buy the former Texaco headquarters in Westchester County as part of an effort to decentralize its operations.

At the same time, Goldman Sachs & Company, a major corporate presence in Lower Manhattan, is planning to move its entire equity trading department to Jersey City, to the $1 billion complex it is building, which includes the tallest skyscraper in New Jersey.

And Marsh & McLennan, the insurance and financial services giant that was displaced by the destruction of the World Trade Center, is completing a deal to move several thousand employees to a new office building on the waterfront in Hoboken, according to real estate executives on both sides of the Hudson River.

These are only the latest developments in a corporate world in which dispersing workers became the order of the day after the attack on the World Trade Center in September. Never again do these global companies want to see themselves knocked out of business for days and weeks, or even hours, by a single cataclysmic event. For instance, Morgan Stanley said yesterday that its tentative purchase of the 107-acre Texaco parcel in Harrison, N.Y., was a way to address "business continuity planning requirements."

This trend presents one of the greatest challenges in rebuilding Lower Manhattan, where more than 20 million square feet of office space was damaged or destroyed in the Sept. 11 attack.

The office vacancy rate has doubled downtown, leaving many analysts wondering which companies will move into the empty space, let alone any new towers that might be built.

M. Myers Mermel, chief executive of Tenantwise.com, a real estate company, estimates that 23,000 jobs went to the suburbs from downtown after Sept. 11 and that another 144,000 jobs are in jeopardy in a second wave of departures.

"Goldman's decision is a significant setback because it affects the downtown core of financial services," Mr. Mermel said. "It's not so much the number of jobs that's significant, but the kind of jobs. Equity trading is the heart and soul of any investment bank."

Of course for a number of years, these companies have engaged in what one real estate developer called a "corporate diaspora" in which many companies dispatch various operations to the hinterlands. Most of these companies are not abandoning New York altogether.

Indeed, Marsh & McLennan, Goldman and Morgan Stanley will still have thousands of employees downtown and in Midtown. But the concentration of offices in an urban corporate campus that was all the rage a few years ago is out. Dispersal is in.

Companies are looking at Long Island City and other parts of Queens, as well as the suburbs. Empire Blue Cross and Blue Shield, a one-time World Trade Center tenant, is moving employees to Midtown and Brooklyn. American Express has moved employees to two sites in New Jersey, but plans to move back to some of its space at the World Financial Center.

Deutsche Bank is planning to build a backup operation at a waterfront complex owned by Mack-Cali Realty in Jersey City. And Instinet, the world's largest electronic trading network and a former trade center tenant, has already completed a deal to build its backup trading facility at Harborside in Jersey City.

In response, city and state officials have scrambled to assemble a treasure chest of tax breaks and other incentives to entice companies into remaining downtown, or to move there. They are also promoting less expensive locations in downtown Brooklyn and Long Island City as alternatives to New Jersey and Connecticut. But government officials and urban planners say that the downtown economy must continue to diversify.

"I don't think that anyone has disputed the fact that we have to do anything we can to ensure that Lower Manhattan remains the financial center of the city," said Daniel Doctoroff, deputy mayor for economic development. "But the Lower Manhattan of the future also has to be a 24-hour community filled not just with financial firms, but also with residences, arts, culture and other things. It's also incumbent on us to find alternative space in the five boroughs for corporations wanting to decentralize."

Jonathan Litt, senior real estate analyst for Salomon Smith Barney, said that companies were smart to move employees, data centers and technical offices to a variety of sites that are not all on the same power grid in the event that one is knocked out of service. But he questioned the decision by Goldman Sachs to move top jobs at the firm to New Jersey, saying many employees might leave because of commuting problems.

Goldman Sachs, whose headquarters is downtown, had a voracious appetite for real estate in the 1990's as it set about building a corporate campus in Lower Manhattan. But in 1999, the investment bank bought three development parcels at the Colgate site in Jersey City, and more recently, began building a 42-story tower there for a backup trading floor and a training center. Recently, however, the company surprised many analysts and city officials when it decided to move some of its moneymaking divisions as well to Jersey City from 1 New York Plaza, where its lease expires in 2004.

"We have decided to relocate all New York-based equities and equities-related employees to our new 30 Hudson complex in Jersey City," an internal memo circulating at Goldman announced last week.

Morgan Stanley was a major tenant at the World Trade Center and was building a third office tower at the northern end of Times Square. But after the September attack, the investment bank decided to sell the tower at Seventh Avenue and 50th Street to Lehman Brothers, a major tenant displaced from the World Financial Center. At the time, Morgan Stanley said it did not want its trading and backup facilities to all be within a single block in Midtown.

Yesterday the investment bank announced that it had reached a preliminary agreement to buy the Texaco headquarters in Harrison, N.Y., which includes a 750,000-square-foot office building. The company said that most of its 14,000 employees in New York City would probably remain there, but that about 2,000 workers would be moved to Harrison, where the company plans to set up a backup data center.

Marsh & McLennan was a major tenant of 1 World Trade Center. Like Lehman Brothers, the company has taken space in Midtown. But after scouting the New Jersey waterfront for a suitable location, Marsh is close to completing a deal to move about 2,000 employees to Hoboken.

Copyright 2002 The New York Times Company