(FORTUNE Magazine) – When terrorists struck New York City and Washington, D.C., in September, business people were on the frontlines. As a nation, we will struggle to properly memorialize the thousands who have perished. As a business magazine, we offer eulogies for a cross section of our community. Some of these people had not been located as FORTUNE went to press. We, of course, pray for miracles and promise to update you if we learn more.

David Alger Fred Alger Management

David Alger was known around the world for his stellar investments and regular CNBC appearances. But to his current and former employees--he helped launch the careers of Marsico Funds' Tom Marsico and Janus' Helen Young Hayes and Warren Lammert--he seemed like a man who had energy for everything. One minute he was busy overseeing one of Wall Street's most successful fund families, the next he was organizing elaborate games of trash-can basketball to help the office unwind. "Some people live intensely," Lammert says. "David was one of them."

Alger, 57, started in 1971 as an analyst with Fred Alger Management, a company founded by and named after his older brother, already an investing star. In 1992 he wrote Raging Bull: How to Invest in Growth Stocks, long before growth stocks and market optimism were fashionable. He became president and chief investment officer of the fund company in 1995. That same year, his Alger Capital Appreciation fund returned 78%, making it the top performer.

Fred Alger Management had 55 employees in the World Trade Center; at press time, more than half were still missing. Once semi-retired, Fred Alger has resumed active management of the company.

David Angell; Lynn Angell Paramount TV; Philanthropist

On Sept. 11, the Angells were headed from Boston to Los Angeles to attend the Emmy awards. Frasier, which David co-produces, was nominated for ten awards, including Best Comedy. The couple had been married 30 years and had devoted much of their time together to philanthropic causes.

Hillsides, a home for abused children, was one frequent recipient of their generosity. The Angells helped fund a new building for the charity and paid for one of the children to attend private school. Lynn, 52, formerly a librarian at L.A.'s Campbell Hall school for 11 years, passed her compassion on to her students, asking them to donate toys and books to Hillsides. (Campbell Hall recently named its children's reading room after the couple.)

David, 54, was well known for "providing some of the most sophisticated, intelligent comedies on television," says Matt Roush, a critic at TV Guide. But the Emmy winner was also a great mentor, guiding young writers through the Hollywood system. "He was just nice, you know?" says Steven Levitan, a writer for Frasier who left to create Just Shoot Me. "In this business, that's so refreshing."

Joseph J. Berry Keefe Bruyette & Woods

Colleagues say Joseph Berry, 55, was a pillar of his investment bank. A native New Yorker educated at Queens College and St. John's, he taught high school in Queens before joining the sales group of Keefe Bruyette in 1972. He eventually worked his way up to COO and co-CEO.

Former associate Rock Tonkel, now an executive at Friedman Billings Ramsey in Arlington, Va., says that Berry was "a key reason the company made it through some very hard times," including the departure and retirement of the firm's founders and an insider-trading scandal that preceded his appointment as co-CEO along with John Duffy, in 1999. "Joe was a solid individual," Tonkel says.

Berry was married and had three children--including a son who also worked at the firm but is not among the fatalities. Almost 70 of Keefe Bruyette's 172 World Trade Center employees, including four members of the company's executive committee, were missing as FORTUNE went to press.

Thomas Burnett Thoratec

When word emerged that Thomas Burnett had called his wife, Deena, to tell her that he was going to try to "do something" to stop the hijackers aboard United Airlines Flight 93, none of Burnett's friends or colleagues were surprised. "Nothing was insurmountable for Tom," says former colleague Robert Riley. "He just had a commanding way--he was always in charge."

Burnett's boss and longtime friend, Keith Grossman, adds, "I don't doubt for a moment that Tom was not only involved but led the effort." It was this self-confidence and magnetism that made Burnett, 38 and a father of three, a rising star at Thoratec, the $30-million-a-year medical device company in Pleasanton, Calif., where he served as senior vice president and chief operating officer. Says Grossman: "He was, in short, exceptional."

Peter Gay Raytheon

Bill Swanson first met Peter Gay at defense contractor Raytheon's Andover, Mass., plant, when Gay was a young engineer testing Patriot missile radars. Swanson, now president of Raytheon's $8-billion-a-year Electronic Systems business, recalls Gay as a bright problem-solver with a sly sense of humor--he was fond of pulling pranks on his boss. He clearly understood both the engineering and the operational sides of the business. "It takes a special talent to run a plant," Swanson says. "If you asked him to do something, you could take it to the bank."

A vice president and manager of the Andover site, Gay, 54, was on his way with two colleagues to visit the company's California facilities when American Airlines Flight 11 crashed into 1 World Trade Center. (Another Raytheon employee was on the plane that hit the Pentagon.) Says Swanson of the 28-year company veteran and father of three: "He was an outstanding natural leader."

Neil D. Levin Port Authority

In late May, Neil Levin, the 46-year-old new executive director of the Port Authority of New York and New Jersey, told a reporter that "the moon and the stars are aligned." He was referring to the working relationship between the two states, but he could have been talking about the success that his agency--which manages New York City-area airports, tunnels, bridges, and the Port Authority Bus Terminal--was enjoying. He had embarked on a sorely needed $9.5 billion capital improvement project--the largest in the agency's history. And real estate developer Larry Silverstein would soon lease the World Trade Center, which the Port Authority owned, for $3.2 billion.

Long Island native Levin--a former vice president at Goldman Sachs who had also served as the New York State superintendent of banks and superintendent of insurance--was reportedly on the 106th floor in Tower One when the hijacked jet hit. At press time more than 100 of his 7,000 employees were also unaccounted for.

Daniel Lewin Akamai Technologies

When he was 28, Daniel Lewin helped found one of the companies that shaped the modern Internet. Before his 30th birthday, he was a billionaire. That may seem young, but Lewin, a passenger on American Airlines Flight 11, was used to performing beyond his years: In his early 20s he was an officer in the Israeli Defense Forces.

Lewin, 31, was chief technology officer of Akamai Technologies, a firm he started in 1998 with one of his MIT professors. The firm, whose market cap once topped $25 billion and which FORTUNE described as "the quintessential Internet company," helped speed up the Web by distributing a site's content over multiple servers. On the day of the tragedy, news organizations such as CBS News, the Associated Press, and the Los Angeles Times used Akamai technology to keep their Websites running. Says Marc Andreessen, chairman of Loudcloud and creator of the first Web browser: "The architecture of the Internet is emerging in part because of Danny."

Bill Meehan Cantor Fitzgerald

Early on Tuesday morning, an editor for TheStreet.com sent an instant message to Bill Meehan, seeking to confirm that the chief market analyst for Cantor, the nation's leading Treasury bond trading firm, would be filing a midday column for the popular business Website. "Yup," Meehan responded from his office on the 105th floor of the World Trade Center's north tower. A few minutes later his editor looked down at her computer and saw the chilling message: "Wmeehan100 signed off at 8:49:35."

One of Wall Street's media stars (in addition to his daily TheStreet.com column, he was a regular on CNBC and CNN), the 49-year-old father of three proved an ideal TV commentator, thanks to his easy manner and blunt views. "He spoke his mind," says CNBC anchor Ron Insana. "He had very strong opinions"--especially when it came to the market. He had been deeply (and correctly) pessimistic for months prior to the downturn. In person, however, the Bronx native was famously upbeat. Says Teresa Shorten, to whom he was once married and whom he had known since third grade: "He embraced life with gusto."

Lisa Raines Genzyme

As an influential lobbyist for drugmaker Genzyme, Lisa Raines was passionate about biotechnology and a "tremendous advocate" for the Cambridge, Mass., company, says its CEO, Henri Termeer.

Raines, 42, perished on American Airlines Flight 77, which hit the Pentagon. Her most lasting professional legacy will be the FDA Modernization Act. Working closely with Massachusetts Senator Ted Kennedy, she acted as a key behind-the-scenes broker for the 1997 measure. She pushed hard for language that would fast-track drugs that treat life-threatening illnesses. "When you think of the AIDS and cancer drugs that were approved more quickly under the provision," says friend Nick Littlefield, an attorney who once worked as Kennedy's chief of staff, "you really have Lisa Raines to thank."

CONTRIBUTORS Matthew Boyle, Eryn Brown, Peter Elkind, Jerry Useem, Alynda Wheat