By Patrick Thomas

Frances Frei always thought she was going to be a college basketball coach. Now, she's coaching companies.

Uber Technologies, Riot Games and WeWork all hired her to fix their cultures. Her job was to improve management, encourage gender equality in hiring and set up internal training programs. She has also worked to make Harvard Business School, where she is a professor of technology and operations, more gender inclusive. She took leave from Harvard to work full time for Uber before returning in 2019.

She credits several of her closest colleagues at Harvard Business School with pushing her to take on larger leadership roles at the school and at some of the largest companies in the world. She applied these lessons to a book titled "Unleashed: The Unapologetic Leader's Guide to Empowering Everyone Around You," that she co-authored with her wife. It was released on June 2.

There was a time before Harvard when a passion for sports dominated her life. She was the captain of her college basketball team at the University of Pennsylvania and planned on pursuing a coaching career until she tore her anterior cruciate ligament in a pick-up game while earning her Ph.D from the University of Pennsylvania's Wharton School. The injury forced her to focus on academia.

"It really felt like a change in my identity," she said. "People knew me as an athlete instead of knowing me as an academic."

Once she got to Harvard Business School, Ms. Frei says she was enlisted in the early 2010s to change the culture after the school observed that not all students were equally thriving in the classroom. After interacting with students, tweaking the curriculum and clamping down on off-campus activities, she said the culture shifted.

"There were great discrepancies on grade point average and satisfaction between men and women," she said. "We immediately set out to close those gaps. There was no doubt the culture changed."

Companies came calling, asking her to address their workplace issues. In 2017, Uber hired Ms. Frei as senior vice president of leadership and strategy. In 2018 she was hired by video game developer Riot Games as a senior adviser to improve the company's diversity and culture.

"With her help, we broke down the foundations of the Riot culture and rebuilt them with inclusion as a cornerstone," a spokesman for Riot Games said.

WeWork, facing criticism that it had no female directors, said last year it would appoint Ms. Frei to the board of directors after the completion of its initial public offering. The IPO failed and the board seat disappeared with it.

Here are four of Ms. Frei's most trusted advisers:

Anne Morriss

Co-founder of The Leadership Consortium

Ms. Frei leans on Ms. Morriss, her business partner and wife, for guidance every day. Ms. Frei said she hasn't worked on a major project without her in a decade.

"She's the person who helps me with my true north in terms of values and priorities," Ms. Frei said of her wife. "I married up, I try to be worthy of her every day."

She said Ms. Morriss does her best work in the morning while Ms. Frei prefers to work into the night. She said that between the two of them they are a 24/7 operation. The two met while Ms. Morriss was an M.B.A. student at Harvard and married in 2006. They live in Cambridge, Mass., with their two children, ages 12 and 8.

"Frances is a force of nature. It's been the privilege of my life to play any role at all in helping her have impact in the world," Ms. Morriss said.

Youngme Moon

Professor of business administration at Harvard Business School

Ms. Frei met Ms. Moon on their first day at Harvard Business School in July 1998. She said the two worked together on changing the culture of Harvard's business school in the early 2010s.

"We were there for each other every step of the way," Ms. Frei said. "I learned what a team was with her: to accelerate audacity and calm each other's insecurities."

Ms. Frei said Ms. Moon encouraged her to work for Uber when many other colleagues were hesitant, she said. Ms. Frei said her colleague also challenges her in smaller ways, suggesting she teach new classes at Harvard when it's common for some faculty to want to keep teaching the same class over and over again.

"She really stoked my audacity and doesn't like it when she thinks I might be limiting myself," she said.

James Cash

Retired Harvard Business School professor, former director of Walmart and Microsoft

Mr. Cash, a retired Harvard Business School faculty member and board member for Walmart and Microsoft, reached out to Ms. Frei and said he wanted to meet her. Ms. Frei says he wanted to make sure she was investing in her personal life and professional life outside of school. She says her most important takeaway from their conversation was that she learned the importance of proactively reaching out to others and becoming a mentor.

"He just asked me about my life and how I'm preparing for the future. He became deeply invested in my life," she said. "People who will say that I'm their mentor in any way, chances are I proactively reached out to them, and that's what Jim did with me."

Nitin Nohria

Dean of Harvard Business School

Ms. Frei was concerned she would be disloyal to Harvard if she went to work for Uber in 2017, but it was the leader of the school, Mr. Nohria, that encouraged her to do it. She credits Mr. Nohria with pushing her to take on more of a leadership role at the school and to pursue consulting work at high-profile companies, including Uber, Riot Games and WeWork. She says he also emphasized the symbolism of what her title at Uber would mean and urged her to seek the title of senior vice president of leadership and strategy at the company.

"My title at Uber was deeply important to him. I didn't care what my title was, he said 'oh no, you need a title that is right smack in the middle of the organization,"' she said. "That was a moment when it came to a head, the symbolism of what we're doing matters greatly."

Write to Patrick Thomas at Patrick.Thomas@wsj.com