Maggie Wilderotter, former CEO of Frontier Communications and a former senior executive at both Microsoft and AT&T, remembers the day that her mother called her at work to report that her husband, Jay, was up on the roof with their 14-month-old son.

As she recounted at the recent Wharton Leadership Conference, she called her husband in a panic. He answered from a portable phone (this being the days before everyone had cell phones) and confirmed it was true.

“I said, ‘Honey, it’s not safe,’” said Wilderotter. “He said, ‘Maggie, it’s a one-story house, and he’s not going anywhere.’” Further conversation revealed that he had used the loops of the baby’s Oshkosh overalls to actually nail him to the roof.

Wilderotter could hear her son happily chattering away in the background. What was her response at learning that the baby was nailed to the roof? “OK. I’ll see you at dinner.”

For Wilderotter, the incident — although it has its funny side — represented a signature moment of “letting go” and allowing the other parent to truly parent. She explained that she had decided, early in her career, to let her husband raise their children and take care of the house, which she noted was very uncommon in the early 1980s. She said she does not believe that the much-touted work-life balance is actually possible. “When you’re the CEO of a large company, or a growing company that you’re building, you can’t do it all.”

Wilderotter added with a smile that her son Chris — the baby on the roof — grew up to become a firefighter paramedic. “He’s on roofs all the time. And he turned out just fine.”

Going Wireless

Introducing Wilderotter at the conference, Wharton management professor Nancy Rothbard commented that she was “among the rare group of women who have really broken the glass ceiling and risen to the upper echelons of leadership in a large public U.S. company.” Wilderotter often appears in Fortune’s annual survey “The Fifty Most Powerful Women in Business,” and a 2015 CNN report identified her as the best-performing female CEO in the S&P 500 for 2014-2015.

Wilderotter began her career in the late 1970s as an accounting supervisor at the startup software company Cable Data (now DST) in Sacramento, California. She got the position by answering a newspaper ad. (“For you millennials in the room, that’s how we used to do it,” she said.) Cable Data provided software and services to “this new industry called cable television,” she noted. “I started my career at two intersecting fields that formed the foundation for both the information and the entertainment revolutions.”

During her 12 years at Cable Data, Wilderotter rose to become the senior vice president and general manager of the cable business in the U.S., Canada, and Europe. She credits the company’s founder, the late Bob Matthews, with being a valuable mentor and sponsor “before there were labels for those activities.”

“Someone’s belief in you and your abilities can truly change your life…. He practiced opening doors,” she said.

While at Cable Data, Wilderotter had her two sons, now 29 and 32. “Nothing else shaped leadership skills like children,” she said. “I learned the vital importance of modeling behavior, multitasking, and flexibility.” To those lessons, she added humility: “Nothing like when your kid spits up on your boss.”

“The Bell heads at AT&T referred to us at AT&T Wireless as the ‘Brat Pack.’”

After Cable Data, Wilderotter moved into the wireless business as regional president of McCaw Cellular. She managed the Cellular One brand in California, Arizona and Hawaii. When Cellular One was sold to AT&T in 1994, Wilderotter became executive vice president at AT&T Wireless. (She also became CEO of AT&T’s aviation communications business, helping to launch the first wireless phone service for commercial airliners.)

The addition of the wireless group to AT&T brought some interesting culture clashes, as Wilderotter described. McCaw Cellular had been “perpetual-motion, high-growth,” whereas AT&T was “a methodical 100-year old organization…. The Bell heads at AT&T referred to us at AT&T Wireless as the ‘Brat Pack.’”

In Wilderotter’s view, each organization brought strengths to the table. “The wireless unit taught Ma Bell about the power of entrepreneurship, performance-based pay and macro-leadership versus micro-management. But AT&T taught us that guidelines and processes aren’t all that bad.” She noted, too, that AT&T’s vast capital resources “sure beat begging investors for more money.” She added that the power of the AT&T brand was “awesome.” She noted that in a national survey of the time, 46% of Americans believed that AT&T was their wireless provider, months before the company had actually acquired a wireless division.

At McCaw and AT&T, Wilderotter said she learned key leadership skills: “the importance of communication and customer relationships; the value employees create when they’re motivated, focused, empowered, and respected.” She noted that she was overseeing 15,000 employees nationwide and that her business was growing at 200% year over year. “I figured out the formula for pulling diverse individuals together to accomplish bodacious goals.”

Wilderotter noted that she believes women have “a natural advantage in customer-facing and service businesses” like telecommunications. She quoted from Marie Brenner’s 2000 book Great Dames: “Women [are] hardwired communicators, Olympic listeners…. We revel in the indirect. We take in the experiences of others, absorb information and secrets, a hidden code.”

Microsoft: The Thousand-Pound Gorilla

Wilderotter’s next corporate stint was as CEO of Wink Communications. “The opportunity to be CEO of a technology startup that was focused both on the cable and wireless industries was just too good for me to pass up.” But one of her biggest challenges at Wink was having Microsoft as a competitor. Microsoft was “the thousand-pound gorilla even back then,” (the late 1990s).

After the frustration of losing two large customer deals on the same day because of Microsoft equity investments in both companies, Wilderotter decided to try to get Microsoft to become a partner. She achieved that partnership, forging a strong business relationship with Bill Gates and Microsoft’s chief research and strategy officer Craig Mundie. The alliance would prove significant later on: after selling Wink to Liberty Media in 2002, she was invited to join Microsoft as its senior vice president of global business strategy.

“Someone’s belief in you and your abilities can truly change your life…. He practiced opening doors.”

“I was the highest-ranking woman at Microsoft, a role I took seriously. Especially in mentoring other women in the organization, again opening more doors,” she said.

She described her two-year Microsoft tenure as a whirlwind. “I went from running a small U.S.-based public company with 125 employees, to one of the largest global leaders in the world who at the time had 56,000 employees.” After a year, she was promoted to running a $5 billion-dollar division in charge of government and education customers worldwide. “The public sector was either the number one or number two customer of Microsoft everywhere they did business,” she noted.

Among the takeaways from her Microsoft years, Wilderotter listed, “Never take your customers for granted. They may love your products, but if you don’t show them the love, they will buy future products from anybody but you.” She also noted, “Smart people with high IQs are not always the best people to get the job done.”  She elaborated that while Microsoft had “a wonderful culture focused on input and debate, at all levels, on all topics, all the time,” the drawback is that this can hinder progress.

Yet Microsoft today is still a “force to be reckoned with” because of its healthy balance sheet. “Just look at the [recent] LinkedIn deal…. Microsoft has over a hundred billion dollars in cash. They can afford to place big bets … and invest in future opportunities.”

The Next Frontier

Of Frontier Communications, from which Wilderotter retired this year, she observed, “Those 11 years were wonder years for me. I took a sleepy rural telephone company only focused on landline service and built it into a Fortune 250 company.” She recognized potential in Frontier at a time when many others did not: “Frontier had a strong foundation, a network that would support a new technology called internet service. Since I was the head of global strategy for Microsoft, I had a very good view over the next 10 years that Internet was going to be sort of important.” She noted that in her final year as CEO, the total shareholder return delivered was 85%, the highest in the industry.

“I took a sleepy rural telephone company only focused on landline service and built it into a Fortune 250 company.”

While at Frontier, Wilderotter again broke glass ceilings. When she joined the company she was the only woman among the top 200 senior leaders. Today, she says, 40% of Frontier’s top leaders are diverse.

She also worked to achieve diversity on the board, in the process replacing 10 of the 12 independent members in her first 18 months as CEO. “It was one of the best decisions that I made,” she said, noting that the new board had “five women, three African-Americans, and five men, all of diverse backgrounds and capabilities, and all passionate about helping me succeed with the company.”

Wilderotter herself sits on several boards today, including those of DreamWorks Animation, Hewlett-Packard, Costco, Juno Therapeutics, Chobani Yogurt, and Cakebread Cellars Winery. She said she has served on 28 public company boards and several private ones during her career. Wilderotter has also placed several women on boards and receives many requests. Female representation remains a challenge: the 2020 Women on Boards Gender Diversity Index of Fortune 1000 companies reported that in 2015, only 17.9% of corporate directors were women.

Wharton’s Rothbard noted that an interesting fact about Wilderotter is that she is not the only CEO of a major corporation in her family. Her older sister, Denise Morrison, is the CEO of Campbell Soup Company. Said Rothbard, “Having a daughter of my own, I was very curious to learn what was in the water they were drinking at your house growing up.”