(FORTUNE Magazine) – Don Spieler, 64, had a good run. After 33 years at Kodak, where he had become president of the company's Mexico operations, it was time to retire and return to his hometown of Rochester, N.Y. Spieler was excited by the idea. Like many executives his age, he saw retirement as a chance to give something back, to volunteer. In Mexico he had served on the national boards of Junior Achievement and the Special Olympics. He was a two-term president of the American Chamber of Commerce of Mexico. He figured nonprofit agencies in Rochester would be thrilled to get his combination of business acumen and volunteer experience.

So Spieler eagerly stopped in at the Rochester chapter of the United Way and met with the director, who seemed very happy to have him aboard. Spieler had envisioned joining a committee to evaluate the group's grantees or sitting on the board of directors. It wasn't until a couple of weeks later that a United Way staffer called with Spieler's assignment: fundraising. "That's not what I'm interested in at all," Spieler responded, bewildered. He hadn't even mentioned fundraising during his interview. "I was pissed off," he says today.

Over the next two years, Spieler went to seven different nonprofit organizations; at nearly all, he was asked to do work that was boring or that ignored his expertise as a businessman. One organization wanted him to volunteer as a two-day-a-week office manager. Or he could attend community meetings and write up minutes for the Chamber of Commerce. "I felt like a trainee again," Spieler says. "I found an entrenched group of agencies that did not accept the skills I could provide for them." Eventually he signed on with the Service Corps of Retired Executives, which pairs former businesspeople with young entrepreneurs. After four years, he's running for the agency's national board.

Get ready for a big bang. The worlds of business and nonprofits are about to collide. The leading edge of the 76-million-strong baby boom is beginning to retire--and shows no signs of going gently into the sunset. This new wave of retirees is leaving work in the wake of the biggest bull market in history. Accordingly, an unprecedented number will have been captains of industry or successful entrepreneurs. "There's a much larger group of skilled people looking for second acts," says Marc Freedman, founder of Civic Ventures, a San Francisco group that focuses on senior volunteers. Although many of the new retirees will move effortlessly into volunteerism, others will run for the golf course or part-time jobs if they are asked to stuff envelopes or hand out juice and cookies at the local hospital. "Volunteers in general are not given very challenging work," says Nan Hawthorne, editor-in-chief of CyberVPM.com, a volunteer-management network.

A challenge for the nonprofits is that so many business people are retiring at a much younger age than their parents did. Civic Ventures says the proportion of men 62 and older in the work force has dropped from 81% in 1950 to 54% today. The image of old men doddering around the back nine or puttering in the toolshed has been replaced by a much more vibrant picture of retirement: active citizens returning to work part-time, doing some consulting, or volunteering. In 1998, 48% of Americans ages 55 or over volunteered, according to Independent Sector, a Washington, D.C., group that monitors the nonprofit field. "A lot more people are going to get involved in helping," says Pat Gilbert, director of volunteer programs for OASIS, a national senior organization in St. Louis. The question is, how long will they stay involved if their work is drudgery?

Ed Kahn had been a group president at a FORTUNE 500 consumer-products company overseeing a $1-billion-a-year business. After that he managed two small, successful consumer-products companies. Then, following a 35-year career, he decided to retire. Kahn identified ten organizations for which he would have liked to volunteer--"among the most well-known public-service organizations in the Philadelphia area," he says--and wrote them letters detailing his interest and experience. He had worked for large and small companies. He knew how businesses were run. He was seeking nothing in return. Was there anything he could do to help? Three organizations did not respond. Six sent letters thanking him for his interest, but telling him that there was no place for him. He had one meeting with a man who seemed to have work for him. Weeks later, the director called back to say the board had filled the job with a paid staffer. Kahn was 0 for 10. "You want to give," he says, "but after a while I sat back and thought, 'Wait a minute. Why fight the battle?' It was nuts."

Three months later Kahn was back in business, having started a publishing company. He had no problem finding people interested in his skills once he reentered the private sector. "I approached people and was welcomed with open arms for what I could contribute," he says. Volunteering, he adds, "felt like another world." Susan J. Ellis, president of the volunteer management firm Energize Inc., agrees: "It really is a Mars and Venus thing." Then, acknowledging that the clash involves more than gender, she corrects herself. "This is Pluto and Neptune," she says.

Should we be surprised that business people and nonprofit veterans don't see eye to eye? The differences between them are profound. Nonprofit companies tend to be bureaucratic, with boards that oversee every initiative. They are often willing to lose money in the course of fulfilling a public-service mission. The freewheeling, self-directed atmosphere of big business is nowhere to be seen. "It can be frustrating for executives who are used to having people do as they say and respond quickly," says Connie Pirtle, director of Strategic Nonprofit Resources in Washington, D.C.

High-powered executives sometimes have a hard time adjusting to the limited resources available to a volunteer organization. Arthur Kahn, 69, former chairman of the Philadelphia law firm Schnader Harrison Segal & Lewis, went to Romania as part of a program that helps budding democracies smooth out their legal system. He noted with amusement that he had to learn how to send his own faxes and place his own phone calls. Susan Howlett, a Seattle consultant who advises nonprofits, was hired by a Microsoft retiree who wanted help organizing strategic planning for a local group. He said he wanted to complete the project in three to four weeks. Howlett thought about what revamping the organization's business plan would entail. All donors would have to be contacted. They would have to review the mission statement, redefine the group's goals, and look at its place in the community. The board would need this information before it could make recommendations. Four weeks? Try four months. "The Microsoft retiree was shocked," Howlett remembers.

It would be one thing if it were just a matter of doing business differently. But there's also the issue of egos. Successful business people who volunteer often have a vision of themselves generously dispensing advice as they descend from the mountaintop. Miriam Buhl directed a New York City bar association program to place retiring lawyers in volunteer posts. That gave her plenty of exposure to know-it-all New York lawyers, like the federal judge who arrived at her office one afternoon seeking a volunteer job as prestigious as his paying one. "I think he thought he was going to be running the organization," Buhl says. "He was shocked that he would have to do hands-on work with clients." Buhl is troubled by such condescension, noting that few executives would walk into a for-profit company demanding a leadership role. "That attitude is ungenerous to the nonprofit," she says. "It assumes that what they do is quite simple and not a post that takes a lot of experience."

"Nonprofits do not need a Bill Gates to walk through their doors," agrees Megan Work, a field council manager for the Seattle office of Youth for Understanding International Exchange. "Many of these executives have grandiose ideas of their own skills, and they just end up causing trouble." Work remembers a former executive she met in 1997, when she was the volunteer manager in Seattle's American Lung Association office. The first inklings of trouble arose during the introductory interview, when the executive insisted that he be given a corporate account and a credit card. Later he requested that the association's computers be updated. Finally he asked for plenty of one-on-one contact with the executive director. None of his demands were met, and he stopped volunteering.

Of course, plenty of volunteers do work out. They are fulfilled by their efforts and happy to make a difference, no matter how small. Al Wunderlich, 68, managed a 27-person staff as head of Anheuser-Busch's global tax division before he retired in 1996. Now, as director of the Franklin Neighborhood Community Association in Belleville, Ill., he sometimes mops floors. One day he was interrupted by a knock. A 9-year-old boy wearing a dirty T-shirt and tattered sneakers had a question. "Mr. Wunderlich," he asked quietly, "do you have anything to eat? We don't have anything at home." Wunderlich took the boy to the refrigerator and gave him some food. At times like that, he says, "I realize how much value there is in this kind of work."

For volunteerism to work in an age of retiring boomers, two things need to happen. Nonprofit agencies will have to abandon some of their hidebound practices. And high-powered boomers will occasionally have to get down on their hands and knees.

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