After five years as leader of the biggest experiment in employee ownership in U.S. corporate history, Gerald Greenwald will step down as chairman of United Airlines next week with a single regret: "We have not been copied in any big way."

That's probably not too surprising. United Airlines is not the kind of company that creates a warm, fuzzy feeling on Wall Street or a big following on the management lecture circuit.

At United, not only do the employees own 55 percent of the stock, they also have a strong voice in how the company is operated. This includes representation on the board of directors, giving workers effective veto power over major corporate decisions from mergers and acquisitions to top management appointments.

You don't have to look any further than the selection of James E. Goodwin as Greenwald's successor for an example of how that veto power works. Less than a year ago Goodwin wasn't even in the succession picture. The odds-on favorite to become the next chairman was United President John Edwardson -- until union representatives on the board made it clear they would veto any attempt to give Edwardson the top job. Today Edwardson is gone, and Goodwin, a longtime United executive, is the new chairman.

Tending to employee concerns has also made United prudent in its expansion plans, not wanting to risk layoffs. A company owned by its employees does not tolerate layoffs.

Still, Greenwald thinks it's a system worth copying, particularly among heavily unionized companies. "I think, given our experience, that there certainly are examples in America where a company could take advantage of our experience and structure," he said in an interview.

Greenwald, who spent most of his career in the auto industry before coming to United, acknowledged that American corporations are often slow to change. Thus, he said he's not surprised that other businesses have not flocked to the United model.

"It's not part of the established way of solving problems," Greenwald said of employee involvement. "It's a funny thing, but when an idea comes at a company from elsewhere, there's this period of denial. I think the jury's out."

The biggest skepticism, according to Greenwald, is on Wall Street, where airline stocks traditionally are given little respect and United's gets even less. Over the past five years, United's stock price has tripled, employment has increased from 77,000 to 95,000, and revenue and profits are at record levels.

But on Wall Street, Greenwald said, "we are still viewed as an experiment, and for better or worse we're being put to a standard of perfection. So any time anything goes wrong it's because of employee ownership." He said the best example of that attitude was the Edwardson situation.

Managing an employee-owned company is no picnic for anyone used to a traditional management role. As Greenwald once noted, "employee ownership does not mean unions and management will hold hands around the campfire and sing `Kumbaya.' "

Indeed, Greenwald said employee ownership makes executive decision-making a much more public process. "We've had to allow the public to watch us in training," he said.

And what about dealing with union leaders on the board of directors? "I've come to a view that employees and their representatives have issues and think more like creditors than they do like shareholders," Greenwald said. "They're worried about job security and want to know `How many risks do you want to take with my job?' "

Greenwald said the union board members have not been shy about challenging management. He said some of the early discussions on executive compensation between union members with backgrounds as negotiators and other board members with backgrounds as bankers were worth the price of admission. "I jokingly said we're going to bring in extra revenue by putting up bleachers and selling tickets," he said of the compensation discussions, without elaborating on the debates.

Despite employee ownership, Greenwald is, for the most part, well compensated by industry standards. He said the board members have come to recognize that they have to pay competitive salaries to attract and retain good managers.

Because the company is employee-owned, however, Greenwald said he has never sold any United stock or exercised his stock options. "I didn't want to be seen selling when our ESOP [employee stock ownership plan] employees are not free to sell," he said.

Although the ESOP doesn't expire until next year, there is some uncertainty about its future. Although United's management and most of its union leaders favor retaining the plan, younger employees, especially among the pilots, are not as enamored with it. The reason is simple: Under federal rules governing ESOPs, an employee cannot get money from the stock investment plan until retirement.

The company and employees have already begun discussing ways to preserve the ESOP and its governance rules while allowing some of the money, as Greenwald puts it, to "leech out" to the younger workers.

But this is a problem Greenwald's successors will have to solve.

Come July 13, he's leaving United with plans to travel up the Amazon in Brazil, move to Colorado and run a marathon. After that, he said, "I'm going to guard my free time."

Gerald Greenwald

Age: 63

Born: St. Louis

Education: Bachelor's (cum laude), Princeton's Woodrow Wilson School, 1957; master's in economics, Wayne State University, 1962.

Career highlights: From 1957 to 1979, worked for Ford Motor Co., including a position as president of Ford of Venezuela; worked for Chrysler from 1979 to 1990, including as chief financial officer; in 1991, became managing director of Dillon Read & Co. Became chairman and chief executive of United Airlines in 1994.

CAPTION: (This graphic was not available) UAL Corp., weekly closing stock prices

CAPTION: United Airlines Chairman Gerald Greenwald plans to take a vacation up the Amazon after he steps down next week.