SANTA BARBARA, Calif. — Amid geopolitical uncertainty and the rapid rise of artificial intelligence, executive leadership has become a far less insular affair, according to Lumen Technologies CEO Kate Johnson.

Speaking at the Fortune Most Powerful Women Summit, the magazine’s annual gathering of women executives, in Santa Barbara on Tuesday, Johnson—who took the helm of the telecommunications company in late 2024—said companies now have to make decisions with far greater agility, and that it is no longer realistic to rely solely on internal leadership for tough calls. Instead, she argued, businesses should lean on partnerships across—not just within—C-suites.

“This notion of the boardroom and the conference room that I grew up in—we were rewarded for being right. We had to know our stuff. We had to be the best. We had to come in with a strong opinion. We had to have all the facts we had to master, and that is just not possible in today’s market,” Johnson told Fortune's Diane Brady.

Rather than striving to be right at all times, leaders need to “build a machine” for decision-making, she explained—forming a hypothesis, watching signals, and consulting experts inside and outside the company to enable constant course-correction.

“I’m getting signals every day, and we’re pivoting every day,” she added. “My job is to get a grant and to allocate the capital accordingly, and you have to have a bench of partners that you can go to to deliver those outcomes.”

The shift is already being measured. More than 80% of chief executives of AI-first companies are engaging partners from external or specialized networks to discuss risk and build on one another’s strengths, according to IBM's 2026 CEO Study. The report attributed much of the change to rapid advances in AI and its adoption in the workplace, which have compressed decision-making cycles and pushed companies to break down established boundaries in search of cooperation.

Boston Consulting Group observed a parallel trend: as mergers and acquisitions slow, companies are turning to alliances instead. According to BCG, 60% of surveyed business leaders said joint ventures and partnerships will be more important to growth than M&A over the next three to five years.

Lumen found one such partner in consultancy EY. In June 2025, EY U.S. and Blue Planet formed a strategic alliance to improve autonomous networking with AI, with Lumen as the project's first client. Blue Planet is Lumen's network-automation software subsidiary, and the alliance was framed as a way to help communications service providers put that technology to work.

The connection between Johnson and EY CEO and Global Chair Janet Truncale began spontaneously. Johnson approached Truncale at a Business Roundtable breakfast—an event of the association whose members are the chief executives of major U.S. companies—a few years ago and, hoping to brighten her day, asked: “Will you be my best friend?”

“And I was happy to oblige,” Truncale told Brady.

The exchange changed how Truncale approaches meeting new leaders.

“In the last two years, I’ve frankly tried to pay that forward,” she said, “so when there are new CEOs, I try to reach out and say, ‘Hey, I’ve just been through this.’”

This story was originally featured on Fortune.com.