Union membership slipped last year, and Mr. Sweeney is so concerned that unions are not doing more organizing that he has called a special meeting of union presidents for next month to press them to redouble their recruitment efforts.

During his five years at labor's helm, Mr. Sweeney has made increasing union membership his No. 1 goal. But he voiced frustration that unions were organizing only about one-third of the one million workers he said should be organized each year to restore labor's might.

One A.F.L.-C.I.O. official quoted Mr. Sweeney as telling the nation's union leaders at a closed-door meeting here, "Not only are the numbers totally unsatisfactory, but if we don't begin to turn this around quickly and almost immediately, the drift in the other direction is going to make it virtually impossible to continue to exist as a viable institution and to have any impact on the issues we care about."

The percentage of American workers belonging to unions fell to 13.5 percent from 13.9 percent last year. That is the lowest level since the number of unionized workers peaked at 35 percent in the 1950's. Even though more than 16 million jobs have been created since 1992, the Bureau of Labor Statistics found that the number of union members nationwide has slipped by 200,000 since then, to 16.2 million.

An ever-larger part of union organizing is in government and in the service sector, including hotels and nursing homes. In contrast, organizing has been sluggish in the manufacturing sector, partly because of the fear that companies might close operations if they are unionized.

Labor leaders expressed concern that just 10 of the federation's 66 member unions were doing about 80 percent of the organizing, while many unions continued to do little to attract more members.

"We have a very uneven situation in terms of unions that are committing serious resources to organizing, and therefore the numbers end up being completely unsatisfactory," said Mark Splain, the federation's organizing director.

Several union leaders at the meeting disclosed the closely kept statistics detailing how many workers various unions told the A.F.L.-C.I.O. they had organized last year.

The Service Employees International Union ranked first, reporting that it had organized 70,000 workers last year. In a virtual tie for second, the United Food and Commercial Workers and the International Brotherhood of Electrical Workers said they had each organized about 50,000. Far smaller unions, including those representing painters, roofers and hotel employees, won praise for doing a lot of organizing in proportion to their size.

The International Brotherhood of Teamsters, like the service employees union, has about 1.4 million members, but the Teamsters organized only 22,000 workers last year, less than one-third of what the service employees reported. Union leaders said the Paper, Allied-Industrial, Chemical and Energy Workers Union, with 275,000 members, reported hardly any organizing.

And three powerful manufacturing unions, which led the way in organizing decades ago, are now doing only a modest amount. The United Auto Workers reported organizing 22,000 workers last year, the United Steelworkers of America about 15,000 and the International Association of Machinists nearly 10,000.

Kate Bronfenbrenner, research director at Cornell University's school of labor relations, said some industrial unions appeared to have grown discouraged about organizing because so many manufacturers move operations overseas, or threaten to move them, if they become unionized. She conducted a survey that found that managers at 70 percent of factories involved in organizing drives threaten to close if workers decide to unionize. Workers often say such threats discourage them from voting to join a union.

Leo Gerard, the steelworkers' newly named president, said he saw a simple explanation for why it was easier to organize workers in government offices, hospitals and hotels than in factories.

"You can't threaten to move the public sector out of Ohio," Mr. Gerard said. "You can't threaten to move a hospital or nursing home to Mexico or China."

Mr. Gerard said the main reason unions were not organizing hundreds of thousands more workers each year was the intense anti-union campaigns run by employers. But business executives say more people are not joining unions because many workers see unions as irrelevant and unnecessary and union dues as too expensive.

When Mr. Sweeney became the A.F.L.-C.I.O.'s president in 1995, unions were organizing fewer than 100,000 workers a year. Thanks in part to his prodding, they reported organizing 350,000 workers last year, an increase that Mr. Sweeney said was good but not nearly enough.

The Bureau of Labor Statistics reported that on a net basis unions lost 200,000 members last year, partly because of layoffs, retirements and factory closings.

Several officials of the labor federation said they were convinced that some labor leaders, eager to impress, give artificially high numbers when they report how many workers their unions organize each year.

Many labor experts say Mr. Sweeney has not been more successful in persuading unions to increase their organizing efforts largely because the A.F.L.-C.I.O. is a loose federation and its president has little sway over member unions. The individual unions, and not the federation, do the organizing, although the federation is seeking to serve as a catalyst.

In contrast to the organizing situation, Mr. Sweeney has had major success in persuading unions to do more on the political front.

"The American labor movement in terms of political operations and political juice has showed its stuff," said Mr. Splain, the organizing director. "The issue is, is there a way for the labor movement to duplicate that type of success in organizing?"

Andrew Stern, the service employees' president, said his union was growing at the fastest rate partly because it spent so much on organizing — about $100 million a year, or nearly half the union's annual budget. He said it cost on average about $1,000 to organize each worker.

The hope among many union leaders is that if other unions with more than a million members could match the service employees in organizing 70,000 a year, the labor movement could begin to approach Mr. Sweeney's goal of organizing 700,000 to a million new members a year.

"I see that some unions are organizing more aggressively," Mr. Sweeney said. "We have to really try to build on that momentum."

Copyright 2001 The New York Times Company

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