Kim Fennebresque was burned out on boards. A veteran of several nonprofit boards, including those of community-television station Channel 13, the Rockefeller Brothers Fund, and the American Lung Association, he was looking for a charitable opportunity he'd feel more personally engaged with. After asking around for recommendations of interesting organizations with compelling missions, a friend told him about Justine Stamen Arrillaga, the founder of the TEAK Fellowship, a Manhattan-based program that provides scholarships and support for underprivileged New York City students at top high schools and colleges.

Intrigued by Arrillaga and the program, Fennebresque, the chairman and C.E.O. of Cowen and Company , a New York-based investment bank, hired seven TEAK fellows as interns at his firm that next summer as a way of supporting the group and of finding out more about it. In 2005, he joined the board.

"I had to think about" taking that step, says Fennebresque, who was jaded from previous board stints where he'd observed that board members were removed from the daily workings of the nonprofit. "With the Channel 13 board, one of my best friends was the chairman, and that's why I was on it. It was a classic businessman, society-guy board to be on, but I didn't care about that." In the end, he joined TEAK's board, too excited about the mission to say no.

Joining the board of a nonprofit organization is a time-tested way for successful executives to burnish their social profiles, network with one another, and give back to the community-in other words, to signal that they've made it. But it's not an insignificant commitment. Most boards meet several times a year, usually once per quarter, and most also ask for a minimum annual financial commitment, from as little as $1,000 to well over $10,000 Also, board members may be responsible for raising money from friends and employers. For businesspeople with large, preexisting demands on their time and money, finding the right nonprofit board to serve on-a board they feel merits the commitment-can be a challenge, simply because there are so many choices. New York City alone has more than 27,000 registered nonprofit organizations, according to a 2002 study done by the New York City Nonprofits Project. And few official channels for getting information on and comparing boards exist.

So what's an executive looking to give back to do? Some, like Fennebresque, do their own research to find causes and organizations they're excited about and then approach executive directors themselves. Others take the advice of work associates, or let a board-matching service do the leg work. And still others find themselves serving on boards that have picked them, rather than the other way around.

In 1997, Jackie Adams, then a prominent correspondent for CBS News, got a surprise invitation from a friend, the president at St. John Fisher College in Rochester, New York, to receive an honorary degree from the school. A few months later, Adams got another surprise call telling her she'd been elected to the college's board, even though she didn't even know she'd been nominated. Flattered and looking forward to spending more time with her friend, she said yes, although she now suspects that the honorary degree was part of an effort to cultivate her as a potential member. This wasn't the last time something like that would happen to Adams, either-in 2001, she was invited to join the board of Off the Record Lecture Series, a foreign-policy forum that had previously invited her to speak at several of its events. Again, she didn't know she'd even been nominated for the board, but once again, she assented.

"Now I have been invited to join enough different boards that I've learned how to say no, or recognize the hook when it's in front of my nose," says Adams, a Harvard Business School graduate who is currently a senior counselor at New York-based P.R. firm Burston-Marsteller. Adams says she currently sits on "six or seven" boards, but is now more selective about which ones she agrees to serve on, pursuing opportunities that fall within philanthropic areas she has defined for herself.

Some execs rely on recommendations from colleagues or mentors to decide which boards to join.

Scott L. Bok , co-chief executive of Greenhill , a Manhattan investment bank, worked at the law firm Wachtell, Lipton, Rosen & Katz earlier in his career, and after leaving, stayed in touch with Martin Lipton, one of the firm's founding partners. When Lipton invited Bok in 1997 to join the board of Prep for Prep, a New York-based nonprofit that places minority students in independent schools, Bok said yes.

"He knew I'd been a supporter of the organization," says Bok. "In choosing which nonprofits to work with, a lot of businesspeople take cues from their career mentors. That's what I did."

Sometimes the matchmaker between board and executive is not a work associate or mentor but a third-party board-matching service like BoardAssist or the United Way's board-placement program, Linkages. These services present executives with information about nonprofits with open board seats and give them the opportunity to meet executive directors there. They also give executives information about what kinds of commitments each board requires, in terms of both money and time.

BoardAssist, which works with hundreds of nonprofits and makes 100 matches a year, arranged a match several years ago between George Mattson, a managing director at Goldman Sachs in Manhattan, and Volunteers of America, a national human-services nonprofit. Mattson hadn't explored board service before he got the call from BoardAssist about V.O.A., but it coincided with Mattson, in his words, "feeling successful enough to look around a bit, and wanting to help people who haven't been as fortunate." In addition to the good timing, V.O.A. was a good fit for Mattson, who says "it felt very much like a hands-on, working board, meaning it was a lot about trying to manage and grow a big, complex organization, and a little less about benefits, dinners, and fundraising."

Organizations like BoardAssist can help mediate between charities looking for a board member and potential candidates, many of whom have little time to spend vetting multiple boards, but are also loathe to waste time later on boards that don't fit with their charitable goals and philosophies.

"It takes time, a lot of time" to find the right organizations and then to carry out a board member's responsibilities, says Robert Levitan, co-founder of iVillage, an online community for women, and the co-founder and C.E.O. of Pando Networks, a peer-to-peer media delivery company. Levitan serves on three boards-New York Cares, whose board he joined with a friend; the Executive Council of New York, with whom he had worked on a project and was subsequently asked to join as a board member; and conservation group Rainforest2Reef, which was founded by a friend-and estimates he spends at least an hour a week on board-related activities, including attending meetings, reading materials, calling connections, and asking friends to contribute.

But he says it's all worth it. "I feel blessed and fortunate to have everything I have in my life, and I was brought up with a sense of obligation to give something back," Levitan says. "And it keeps me connected to things that matter on different level from my day-to-day business."

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