When "Equity" arrived in theaters in late July, Barbara Byrne had her name in the credits.

Byrne was a producer for the movie, which tells the story of Naomi Bishop, an investment banker intent on climbing up the corporate ladder. The movie won praise for depicting the biases faced by women who enjoy the power that comes with earning money.

The project is just one of the distinctive ways that Byrne has promoted gender diversity throughout her career. Before producing the movie, for instance, she oversaw the launch of a market index that tracks the performance of women-led companies. She also recently launched an internship program at Barclays for midcareer bankers who want to return to the industry after taking time off — whether to raise children or care for elderly parents, for instance.

When it comes to supporting women in banking, she wants to do more than the usual basics — such as mentoring.

"I try to choose things that have a bigger impact — kind of a puffer effect," Byrne said. "Like a puffer fish, it looks bigger than it really is."

Her work on "Equity" veers outside of the comfort zone of most investment bankers. It relies on the power of storytelling to show the subtle but deeply embedded stereotypes that hold women back in the industry.

In her role as a producer, Byrne helped finance the film. She also offered insight to the actress Anna Gunn, who plays the role of Bishop, about how the investment banking industry works.

Byrne discussed what it's like to run an initial public offering. In the movie, Bishop is faced with the setback of having an IPO go poorly.

She also discussed the social environment on Wall Street. For instance, banks often reward men for their ambition — or their "commanding presence" — but criticize women for appearing pushy, she said.

In one of the scenes, Bishop is told that she's too aggressive and rubs people the wrong way. Instead of getting angry — and validating the criticism against her — Bishop holds back and absorbs the blow.

That's how women navigate the banking business, Byrne said.

"How can you soften your edge, but still have presence so that you can be heard?" Byrne said, acknowledging that women can't "boil the ocean" and change everything at once.

One of the reasons "Equity" is effective is that it doesn't sugarcoat the way women treat each other. It's a thriller that puts women in the same cutthroat roles that are typically reserved for men.

"This is not a sisterhood movie," Byrne said.

Still, if you ask Byrne about her own career path, it's clear that her love of acting and movies is about more than show business.

Early in her career, one of her mentors gave her advice to use "method acting" as a way to build courage and confidence in meetings.

Byrne — known for her outspoken style — was shy in her mid-20s, when she took her first job at Lehman. She describes herself back then as much better suited for a library than a major investment bank.

"I am a forceful personality, but I did not spring from the womb that way," she said.

She credits Harvey Krueger, a longtime executive at Lehman, with bringing her out of her shell.

One interaction, in particular, left a lasting impact. Byrne had prepared a presentation for Krueger to give to the board of a major company.

Krueger turned to Byrne, and asked her if she thought he was capable of giving the presentation. She, of course, said yes.

"So he said, 'Well, why don't you get up there and just pretend you're me?'" Byrne said.

She did — and it worked. Over the next few years, she continued to imitate him, and in the process developed her own sense of confidence and her own characteristic style.

Byrne now offers the same advice to her employees. During big meetings, she sometimes spontaneously hands over control to young bankers — but only when she knows they are absolutely ready. "It's great fun" she said.

Byrne said she often tells young women that they shouldn't worry so much about being liked by their peers, and that the way you get ahead and gain respect in banking is by raising your hand for new opportunities, not fully knowing how they will turn out or whether you're fully prepared.

Women in banking build courage when they encounter rejection without taking it personally or ask critical questions in big meetings. And those experiences develop over time.

"It's important for young women to know this: each day is another page, and it becomes another chapter," Byrne said.

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