(FORTUNE Magazine) – If women are from Venus and men are from Mars, then Rebecca Mark is from another planet altogether. Six years ago she was a 35-year-old student at Harvard business school, nicknamed Mark the Shark for her ferocious ambition. Today the 5-foot 7-inch honey-blond is CEO of Enron Development, the international ventures arm of Houston's hyperaggressive Enron Corp. As a builder of pipelines and power plants, Mark brings electricity to browned-out corners of the earth. From Bogota to Bombay, the lady knows riots. She's dodged bombs. When foreign governments collapse, she digs in her high heels. After Hindu nationalists and their allies canceled Enron's power project in India--the subcontinent's largest-ever foreign investment--Mark reincarnated the deal. "I enjoy being a world-class problem solver," she says. "I'm constantly asking, 'How far can I go? How much can I do?' "

Welcome to the corporate orbit of supersuccessful women: the ones who blast through glass ceilings, achieve otherworldly feats, and take astronomical risks to boldly go where no man has gone before. FORTUNE looked inside hundreds of companies in dozens of industries and found seven women who are the best--better than the men and all other women in their businesses. Charlotte Beers led the most impressive turnaround of an ad agency at Ogilvy & Mather Worldwide. Jill Barad made Barbie the world's most popular toy. Little-known Roberta Williams is the best-selling designer of computer games. Some of these women are chief executives. This is not, however, a gender-bending group of tomorrow's CEOs. Linda Marcelli will never head Merrill Lynch. But as director of Merrill's flagship New York City district, she made FORTUNE's cut because she oversees the top-performing branches in the top market at the top brokerage firm.

The real surprise is how the women reached their pinnacles: They broke every rule imaginable and trashed the conventional wisdom of executive women's groups, career counselors, and other gurus of getting ahead. They didn't plan their careers. They didn't network and still don't--in fact, they despise the word. They don't blend into the corporate culture. They don't whine when the culture works against them, and they never cry, "Discrimination!" They don't play the man's game, literally or figuratively. They don't act like men or think like them. They never dress in androgynous suits and those homely bow ties. And they don't golf. Well, one of them does: Diana "Dede" Brooks, the unstuffy CEO of Sotheby's, one of the world's stuffiest companies. And wouldn't you know, she plays better than most guys, scoring in the mid-80s.

This new female elite is definitely not your parents' paradigm. Remember when executive women used to be overwhelmingly single and childless? All of the FORTUNE Seven have children. Five are married and two, Mark and Beers, used to be. Feminists in no standard way, they flaunt their femininity. As Rebecca Mark says, "It's startling to people when you're attractive and also really smart or extraordinarily good at what you do. You have greater impact. People want to meet you. They remember you." Beers, 61, is a flamboyant flirt who calls CEOs "honey" and "darlin'." She's been known to refer to IBM CEO Lou Gerstner, her largest client, as "that adorable little man." Says Beers: "One of the biggest mistakes women make in business is that they aren't friendly enough."

Which brings us to our title: "Women, Sex, and Power." (About the only loaded words we've left out are "Men and Money"; for more on that, see the following story.) By sex, we mean gender. Unlike so many women, these seven see their gender as a help, not a hindrance. (For some high-powered girl talk on this subject, read the box "Cocktails at Charlotte's.") We also mean sexuality, which these women skillfully exploit. Finally, by sex, we do mean sex. Women who are attractive and successful, particularly in male-dominated fields, sometimes have to fend off suspicions: How really did she reach the top?

Sexual innuendo dogs Mark, in part because several years ago she had an unusual relationship with John Wing, once her boss at Enron. People close to Mark and Wing say they had an affair; both were married to other people at the time. Mark declined to talk about their relationship, and Wing did not return repeated phone calls from FORTUNE. However, friends say that the mercurial and charismatic Wing began as a mentor to Mark, and later turned into a Svengali. After Wing left Enron, Mark assumed his duties of developing power plants. No surprise, rumors have circulated that Mark has had relationships with other Enron colleagues. "Of course they're not true," says Mark, "but it's terribly flattering that people think my life is so exciting. I think all I do is work, travel, and take care of my 11-year-old twins."

It's the Mary Cunningham curse. Sixteen years have passed since Cunningham, a young, blond MBA straight out of Harvard, arrived at Bendix, where she simultaneously became a top corporate strategist and a constant companion of CEO William Agee. Now married, the couple always denied having a sexual relationship at Bendix. But the Mary-and-Bill saga was the talk of the business world, and it remains so titillating that high-powered women to this day carry some burden of proving they did not sleep their way to the top. "There are still so few women in high-powered corporate jobs," says Kathleen Reardon, a professor at the University of Southern California business school and an expert on male-female relations. "When people see something unusual, like a woman who is No. 1, rumors provide a rationale." For women, the dilemma is how to fight them. "Defensiveness causes more rumors," Reardon says. "You know, 'the lady doth protest too much.' "

The FORTUNE Seven are complex, controversial women who have made long--and not always politically correct--marches to the top. Nonconformists to the core, they have unique styles but also share some similarities. Here are five ways they have acquired and kept their power.

THEY USE THEIR SEXUALITY

Most women in business downplay their sex appeal. They seem insistent on being judged like men, repressing a trait they could be using to persuade, win favor, gain power-- okay, manipulate their way to the top. Not these women. Says Barad, decked out in shocking pink from shoes to suit to lipstick: "We never gave up our femininity. We didn't become little men. I don't care to get on equal footing with men." Welcome to the boys' club anyway, Jill. Barad, 45, is expected to become Mattel's CEO next year, making her one of two female chief executives in the FORTUNE 500. (The other is Marion Sandler, CEO, along with her husband, of Golden West Financial, a California S&L.) Like Barad, Linda Marcelli greets colleagues and clients with hugs, sometimes kisses. "If one of my financial consultants is having a problem, I'll put my arm around him," says Marcelli, 53. "A male manager once asked me incredulously, 'You touch your financial consultants?' I said, 'Yeah. What's wrong with that?' " In fact, these women are taking advantage of an odd double standard: Men who touch women risk accusations of sexual harassment.

Charlotte Beers is known for sweeping theatrically into client meetings. Even before hellos are exchanged, she'll drawl to the group, "Now, you're gonna give us this business today, aren't you?" To most men, she's beguiling. Sears CEO Arthur Martinez, an Ogilvy client, says, "I think a lot of male-female business relationships get stilted. What I like so much about Charlotte is that you can have fun with her." Beers's former colleague BBDO International President Jean-Michel Goudard says, "Charlotte, more than anyone in this business, wants to seduce. There's something deep about Charlotte, and also frivolous. She is a woman, a woman, a woman."

It is the women, the women, the women who knock her style. Some say she sets feminism back years. "The criticism really ticks me off," says Beers, who comes across in an interview as intimate, incisive, tough, funny, and a decade younger than her 61 years. A cowboy's daughter from southeast Texas, she first learned to dazzle the crowd when she was in her 20s, teaching algebra to oil-patch engineers. Beers reckons that Southern charm is simply smart business. "Yes, I call CEOs 'honey,' but to me, that's wry Texas humor," she says. "I'm likely to say the most outrageous thing in the room--to liven things up."

Four years ago, Beers seemed an unlikely corporate revivalist. The longtime head of Tatham RSCG, a one-office ad firm in Chicago, she moved into a New York company with 270 offices around the world and famously inbred management. Ogilvy & Mather used to be the class act of Madison Avenue. Then in 1989 it was acquired in a hostile takeover by Britain's WPP Group. When Beers arrived, key Ogilvy veterans had quit. Clients were pulling major accounts. "A lot of people thought Charlotte should have her head examined for going to Ogilvy," says WPP chief executive Martin Sorrell. "And most people thought I was crazy to hire her."

Sorrell, who pays Beers $1.5 million a year plus stock options, acquired a CEO many thought was mercurial, flighty, and disorganized. Instead of talking profits, Beers preached "passion"--the essence, she said, of resurrecting Ogilvy & Mather. She had one big idea to sell to clients: "brand stewardship." Insiders considered it pretentious shtick about the emotional bond between a product and its consumer. Even David Ogilvy, the 85-year-old Scot who founded the agency in 1948, was a skeptic. "I had to shepherd the idea because our own people were unconvinced," says Beers, adding, "I think consensus is a poor substitute for leadership."

She globetrotted, mostly alone, visiting 50 clients in six months. "As a woman, I got in to see people quickly," says Beers. "they were curious about me." Before long she landed two important accounts: American Express, which had earlier yanked its $60 million business from Ogilvy, and Jaguar. During a pitch to Jaguar executives, Beers tossed her own car keys on the table, then rhapsodized about the relationship between an owner and her Jag. She didn't create Ogilvy's award-winning campaign, but it is quintessential Charlotte: a glamorous ode to the Jag, set to the 1961 Etta James recording, "At last my love has come along. My lonely days are over..." She tools around Manhattan in her ice-blue XJ6. Her buddy Martha Stewart drives the same Jaguar in gray.

It's supposed to be a secret, but Beers's No. 2, Shelly Lazarus, is likely to become Ogilvy's new CEO before the end of this year. Lazarus, 48, was the key to reeling in the worldwide IBM business two years ago--the largest account shift in the ad industry. IBM made Ogilvy hot again and helped attract global advertisers such as Kodak and Swatch. (Ogilvy, the sixth-largest ad agency, has billings of $7.6 billion, up from $5.5 billion when Beers arrived.) Beers will probably remain chairman for a while. Says WPP's Sorrell: "I hope Charlotte will work with WPP for life."

THEY DON'T PLAN CAREERS

Not one of FORTUNE's women pursued a career step by logical step. They did what interested them, focusing intently on the job at hand. If they slipped, no big deal; they moved on. When Mattel's Jill Elikann Barad was attending Queens College in New York City 25 years ago, she wanted to become a doctor. Her first time in an operating room, she fainted. She tried acting. Her first job, playing Miss Italian America in a 1974 gangster movie called Crazy Joe, "seemed superficial," she says. Veering into cosmetics and then advertising, Barad arrived at Mattel in 1981 as a $38,000-a-year product manager. Today, as president, she earns more than $1.5 million. "I tell my kids that it's okay not to know what you want to do," says Barad, who is married to a Hollywood producer, Tom Barad, and has two sons, Alex, 15, and Justin, 13. "I think diversity, the idea of trying everything, is important. Somehow all your experiences come together and make you multidimensional."

The variety-show format made a superstar of Barad--and Barbie too. Mattel had a do-nothing brand, with $235 million in annual sales, when Barad took charge in 1982. She refashioned the doll into a versatile career woman--doctor Barbie, astronaut Barbie, executive Barbie, altogether 100 different versions. The ad slogan (courtesy of Ogilvy & Mather): "We girls can do anything." Says Barad: "I really believe that." Barbie is now 37 years old, but hardly mature. Sales of her and her wardrobe increased 25% last year, to $1.4 billion.

Mark too had no idea what she would eventually become. "Opportunities and challenges define your career," she says. "You just have to follow your instincts. Do what excites you. And you don't see the path until you get there." Mark's path began on the family farm in northeast Missouri. Land rich and cash poor, her Baptist parents couldn't afford to pay for college. So Rebecca put herself through two years at Missouri's William Jewell College. Then she transferred to Baylor (where Beers also went to college but did not graduate).

She initially wanted to be a clinical psychologist. But working with juvenile delinquents was "personally depressing," she says--"the antithesis of everything I learned growing up: that you can control your own destiny." In 1978 she entered a bank training program at First City National Bank of Houston and began lending money to energy companies for big, risky development proj-ects. In 1982 she joined Continental Resources, a natural-gas outfit that later became part of Enron.

Winsome when she wants to be, brazen when she has to be, Mark never displayed the modesty that holds women back. She was tough and self-confident when she arrived at Enron; John Wing made her even tougher. A West Point graduate, Vietnam veteran, and onetime General Electric manager, Wing came to Enron in 1985. According to people who know them both, Wing frequently yelled at Mark in meetings and called her a failure. Sometimes he fired her for a few hours, or a few days. This was Wing's way with many people, but no one endured as much as his star student. "There's good and bad in every situation," says Mark, who abhors talking about Wing. Mixing ruefulness with defiance, she says, "John gave me my fearlessness. He taught me not be be afraid to make decisions in intense, difficult, and emotionally charged situations."

When Mark left Enron for Harvard business school, some thought she was crazy to interrupt a promising career. In Cambridge, Massachusetts, she continued to work part-time under contract to Enron. Soon she found herself back under Wing's wing, developing Enron's first foreign project, a cogeneration plant in rural England. "Rebecca was recently separated from her husband," recalls Ken Lay, Enron's CEO. "She had her small twin boys to take of, and still she worked almost full time for us while she went to business school. It was her choice." Fellow HBS '90 grads recall Mark dashing into classes late, overstuffed briefcase in tow; they considered her brilliant. Says Mark Connors, president of Database Publishing Group in Cambridge: "She could read a case study and boil it down quickly. We learned a whole lot from her."

MBAed and back in Houston, Mark was ready to take on the world--literally. Her career path expanded when Wing, who had alienated many people at Enron, left the company. Replacing him as boss of power-plant development, Mark persuaded Ken Lay to create a separate company to build in Third World markets. In 1991 she became CEO of Enron Development Corp. Today Mark has 25 developers working for her; 22 are men. Like investment bankers, they make their money when deals get done. In an average year, Enron people say, Mark can earn over $2 million. She and her group have built plants in Guatemala, China, and the Philippines. They have projects in the works valued at $19 billion, including power facilities in Indonesia, Puerto Rico, and two dozen other countries. (For more on Enron, see "Power Players.") Says Daniel Yergin, a leading energy consultant: "Rebecca is tops in her business. She has some unfathomable source of energy that allows her to crisscross time zones and operate with acuity and focus."

"Really, I'm a warped human being," says Mark, whose dashes of humor are disarming. Her own fuel is exercise. She runs 15 miles a week, at a very human nine-minute-per-mile pace. She skis and rides horses with her twins, Rob and Jared, in New Mexico, where she is building a vacation home. Is Mark gunning for the top at Enron? "As I said, I don't plan my career. Maybe I'm going to run the World Bank, or CARE. I think of my job as one step in a life's work. It'll lead to bigger and different things."

THEY TAKE THE FLAK

All these women have faced opposition and discrimination--bosses who labeled them weak, men who refused to work for them, clients who discounted their opinions. They've survived flak attacks from women as well as men. Says Charlotte Beers: "Early in my career, during my first week at J. Walter Thompson in Chicago, I had a secretary who asked the company for a transfer. She told me, 'No offense, but I want to work for a man who's going to move ahead.' " Beers agreed to the transfer. Two years later, the secretary asked Beers to take her back. Beers did. "I liked her honesty," she says.

FORTUNE's leading women possess an odd blend of optimism and fatalism that yields a remarkably resilient personality. Says Sotheby's Dede Brooks, 45: "I've always believed in fate. Certain things you can control. Others you can't." Brooks's older brother, whom she idolized, died in a motorcycle accident when she was 16. She believes his death gave her the confidence to weather any setback. "Life is about how you deal with adversity," she says. Raised on Long Island and trained as a lending officer at Citibank, Brooks didn't appear to be top-management material when she arrived at Sotheby's 17 years ago. An American girl in a bastion of British men, she hardly knew her Pissarros from her Picassos. Brooks was working in the finance area in 1983 when she caught the attention of Alfred Taubman, Sotheby's new American owner. Walking into a meeting where Brooks was the only woman, Taubman asked her to get him a cup of coffee. "Yeah, I'll get you coffee if you'll Xerox these papers for me," Brooks replied.

"I suppose it was a little bold," she says now. "But Al laughed. We both laughed. I think having a sense of humor is as important as anything to getting ahead."

Boisterous and Doris Day-ish, with a mussy bouffant, Brooks has loosened Sotheby's uptight culture and tightened its bottom line. "I've always taken a lot of flak," she says. Once, after she fired some people and the press labeled her the "Terminator," she displayed a picture of Schwarzenegger, with her face pasted over Arnold's.

Although Brooks deserves kudos for Sotheby's mass-marketing masterpiece, the Jackie Onassis auction, she's had to deflect criticism of her auctioneering style. Aficionados complain about her lack of finesse at the podium. She had never raised a gavel until she began training for the Jackie auction. For ten months she watched videos and practiced with colleagues. "I think I made thousands of people comfortable who had never been to an auction before," says Brooks. "They needed an auctioneer who was direct and kind, not intimidating." The high-priced tag sale rang up $34 million in sales--a triumph. Even so, Brooks plans to keep her day job.

Mark says women need to try hard to roll with the punches: "You can't take things that people say personally. If you do, your confidence goes down, your ego gets in the way, and you don't get the work done. Then you're defeated." Colleagues and competitors alike cite Mark's deft handling of Enron's near disaster last summer in India. A new government, hostile to foreign investors, took over in the province where she planned to build a multibillion-dollar plant. After threatening to "toss Enron into the Arabian Sea," it canceled the project. Mark's job was to salvage the deal. "I was amazed," says Charles Frank, a vice president of GE Capital (GE and Bechtel are minority partners). "The more things went against her, the more determined she seemed to be." Mark spent about 20 weeks in India over the course of the year; last January she agreed on a revised contract with the Indian government.

THEY DON'T BLEND IN

Charlotte Beers maintains that true leaders disdain decorum. "So many CEOs are impeccably logical, but they don't lift your heart," says the diva of Madison Avenue. "They rely too much on the way things should be done. I believe in provocative disruption."

Linda Marcelli concurs: "In order to lead in a man's world, you can't be plain vanilla." A showboat in an ocean of corporate gray, Marcelli, a tall platinum blond, wears loud suits, bright pink lipstick, and lots of gold. Her colorful packaging is but one of many things that make her stand out. She is the only woman among 29 district directors who run Merrill's brokerage offices across the country. Her bailiwick, New York City, generates annual revenues of $300 million. By several measures--total revenues, business growth, recruitment of new brokers--Marcelli ranks first in the Merrill system. "Wall Street is a culture where women find it very hard to deal with barriers," says Paine Webber President Joseph Grano, who used to work with Marcelli at Merrill. "Linda doesn't look at being a woman, having children, and having an unusual living situation as barriers at all."

Two decades ago Marcelli was a teacher in Boston, committed to transforming young lives. When the school where she and her husband, Tony, worked shut down, she reassessed her career. Linda knew she liked managing her family's money. So she applied to be a broker. She interviewed at Paine Webber but says, "Merrill treated me with the most respect."

Marcelli joined Merrill in 1975 and instantly attracted attention. The men couldn't get over this 32-year-old trainee who at home was taking care of two of her own kids, nine foster children, a few former students, a husband, a dog, and two ferrets--and boy, could she sell stocks! A believer in the you-can-sleep-when-you're-dead philosophy of life (Marcelli gets by on four hours of sleep), she threw herself into her work and family with equal elan. Says Merrill Lynch senior vice president Bob Sherman, Marcelli's current boss: "Linda's strength has always been her ability to make people believe, 'If you do this, you're gonna have a better life, more money, and be happier.' She's very sincere about it. She has tremendous empathy for people."

During her early days at Merrill, says Marcelli, "everybody sold stocks by cold calling. But I didn't. I set up personal meetings." Her clients weren't the only people packing the reception area of the Boston branch. "There'd be these children, multiracial and all different ages, coming in and saying, 'I'm here to see my mother,' " recalls Marcelli. "People told me they needed an organization chart for my family." Marcelli's husband Tony, who is 13 years older, told her that he was content playing second fiddle. So in 1980 she moved to where the money was--Manhattan--and became a manager. The Auntie Mame of Wall Street says she used to keep a tarantula named Oscar in her office, "to see what the men who work for me are really made of."

Tony, meanwhile, moved to Florida to help care for his and Linda's sick parents. He also started a tomato business, buying expensive vine-ripened tomatoes from Florida farmers and driving them overnight to Manhattan. For years, Linda worked nights and weekends on the trucks, sorting and delivering. "I'd rush home from work and get out of my suit into sneaks and jeans," she recalls. "I'd have to take long showers each night because I didn't want to go to the office smelling like rotten tomatoes." Today, Marcelli commutes weekends to Florida, and still helps with the business. Lucky's Real Tomatoes ships almost three million pounds of its sun-kissed varieties exclusively to New York City. Order a salad at the Palm or the Union Square Cafe or Le Bernardin, and you will get a taste of Linda Marcelli.

Roberta Williams, 43, is another who contends that only ordinary people blend in. "I never felt like I fit in," says the tiny, waiflike top gun of the computer game industry. "But I felt deep down inside that someday I'd do something really extraordinary or different." Mischievous as a child growing up in California, she rebelled against her father and refused to go to college. She married at 19, had a child at 20; by 25, she was a discontented housewife. One evening, her husband, Ken, a computer programmer, brought home an early computer game. Roberta became hooked, instantly. After playing a few more games, she recalls thinking, "There must be opportunity here."

Ken scoffed at Roberta's notion that designing games was what she wanted to do with her life. She had worked with computers in part-time jobs, says Ken, "and she was never a good programmer." Roberta concurs, but she still badgered him to start a business with her. In 1979, he agreed. They packaged their first game disks in Ziploc bags; their factory was in their kitchen. Today, Seattle-based Sierra On-Line is the world's No. 1 seller of computer games. Ken is CEO; Roberta is chief game designer. The 23 games she has invented, including her best-known King's Quest adventure series, have sold nearly seven million copies, vs. three million for the Miller brothers, the one-hit wonders who created Myst. In February, Connecticut-based CUC International agreed to buy Sierra for $1 billion in stock; under the terms of the deal, Ken and Roberta will continue to run Sierra.

In a field dominated by men, Roberta says she creates games "guys wouldn't think to do": fairy tales instead of Doom-like shoot-'em-ups. Much like a screenwriter/director, Williams concocts a story and its characters, then instructs a team of engineers, programmers, and artists to perform the technical magic. Williams created the first game that blended graphics and text, the first 3-D animated adventure, and the first adventure with a female protagonist. Yes, of course, her women are brilliant and beautiful. In Williams's recent Phantasmagoria, which cost $4 million and took 200 people to produce, newlyweds move into a spooky old mansion. When Hubby becomes possessed by evil spirits, he turns into a demented rapist. The game player's mission is to help lovely Adrienne outwit the demons and get her husband back.

THEY DON'T FAVOR WOMEN

Hard-core feminists might call the FORTUNE Seven queen bees--women who move ahead but don't pull along their sisters. Except for Dede Brooks, who wants to recruit female managers at Sotheby's, these women don't think about affirmative action. They don't try to promote or even hire females. As Jill Barad says, "To get the best person, your approach has to be gender-free."

Charlotte Beers's rule of recruiting is: "Don't hire anyone you wouldn't want to have dinner with." It's pure coincidence, then, that the CEO-to-be at Ogilvy & Mather is a woman: Shelly Lazarus, the level-headed, pragmatic, unpretentious foil to Beers. When she joined Ogilvy 25 years ago, she was the only woman among 100 account managers. Six months pregnant with her first child in 1973, she became the company's first female account supervisor. She has consistently sought out difficult assignments that no one else wanted. Direct marketing was a dud business when she moved into it. "I didn't care," says Lazarus. "I wanted to run something." She built up Ogilvy's direct-marketing unit, and then she turned around the agency's beleaguered New York office. Hoisted to higher-profile posts by Beers, Lazarus looks like an overnight sensation after 25 years.

Following the footsteps of her boss, Lazarus doesn't favor females. She angered working mothers at Ogilvy by forbidding anyone who works part time or flextime to become a senior partner (Ogilvy has 162 senior partners, 63 of whom are women). "Just because you're a woman with a child, you can't be allowed lower standards of performance," Lazarus says.

Despite their toughness, these women try to nurture--we can't avoid the word--all their employees. Mark hosts an annual Christmas party at her home for the 180 people who work for Enron Development. Spouses, kids, and Santa come too. Every Fourth of July, Marcelli invites hundreds of Merrill Lynch's support staff and their families to her fireworks bash in Manhattan. She and a few friends cook themselves. "It's a labor of love," she says. Jill Barad threw a crazy party at her new home in Bel Air, California, this spring. Buses that were supposed to transport 120 Mattel employees failed to show up. After everyone arrived late, a storm blew out the electricity for four hours. Barad's sons spent the evening escorting executives to the bathrooms with flashlights. "It was worse than awful, but it became this bonding experience," says Barad, whose laugh was heard above the din all evening.

Do these women feel balanced? No way. Brooks has been married for 25 years to a venture capitalist and has two teenagers. "I have the most exciting job imaginable, and it's a killer," she says. "I don't have control of my life." Lazarus and her husband, a Manhattan pediatrician, have three children, ages 8 to 22. Though peers consider her the model working mom, Lazarus begs to differ. "Someone once described me as a swan," she says. "I look smooth going across the lake, but underneath, I'm paddling like crazy. I'm happy that I'm fully engaged in all parts of my life. But I don't ever feel satisfied."

Adamantly, these women say no one can expect to have it all, even though they are trying hard. Mark has a live-in nanny for her twins. The nanny and her 16-year-old daughter have spacious quarters in Mark's home, and she helps pay for the girl's private schooling. Recently Mark enrolled Rob and Jared in a school that caters to international students; its flexible curriculum will allow her to take the boys on some of her trips. Still, there's only so much any supermom can do. "A marriage or relationship hasn't been feasible for me," says Mark. "Too many women think they can have a wonderful career, a terrific marriage, happy children, and a great social life. It's just not reality."

When she talks like this, Rebecca Mark doesn't seem to be from another planet. Like most hard-working, high-achieving women, she sounds a little vulnerable. Mark and the other FORTUNE superstars are larger-than-life proof that no matter how spectacular the ascent, life at the top is never comfortable.

REPORTER ASSOCIATES Eryn Brown and Tim Carvell