08/17/2026
“Leadership is not one-size-fits-all. You can’t make any assumptions about people’s views and approach.”
Sierra Signorelli, SEP ’19, likes to say that risk is at the heart of her business. But even as she helps clients navigate uncertainty as a global leader in commercial insurance, she’s proven that she’s not averse to taking risks of her own.
Signorelli was initially drawn to environmental science and the chance to “make the world a better place,” she says. But when serendipity showed her a different way to have impact, she enthusiastically stepped through the door. “Insurance is not just a financial product; it’s really an enabler of progress. I’m passionate about our ability as an industry to help solve some of the world’s most complex challenges.”
Beginning as an underwriter with AIG, Signorelli embraced ever-increasing leadership opportunities, taking her from California to New York, Singapore, and ultimately Switzerland, where she became chief underwriting officer for Zurich Insurance’s commercial lines. But even as her career accelerated, she believed she still had more to learn. “Success can create momentum,” she says, “but it also can create blind spots.”
That conviction led Signorelli to Stanford GSB for the “intensive and immersive” experience of the Stanford Executive Program. “Stanford was a wonderful opportunity to step outside of my day-to-day environment, challenge some of my thinking, and reflect on the kind of leader I wanted to be,” she says. Returning to Zurich, she partnered with Stanford to design leadership programs for the company’s emerging talent.
Now the CEO of both Zurich U.S. and Zurich Commercial Insurance, Signorelli is still guided by her drive to make a difference. “We have the opportunity to help businesses think about their cost of risk, and not only insure it, but help them understand how they can reduce that cost through loss control,” she says. “That saves assets, but more importantly, it saves lives.”
This SEP alum doesn’t see risk as a threat, but as an opportunity.