Carolyn Everson, Facebook’s most prominent liaison to the world of advertising for years and through thick and thin, is leaving the company.

“I have left Facebook,” Everson posted to Facebook on Wednesday. “I am extremely proud of what we set out to accomplish but way more proud of my team and the support we showed each other, especially in difficult times. I always said no one will ever mention at my funeral the amount of revenue I oversaw. But hopefully one day someone will say my legacy at Facebook was in how I showed up for my team, for our clients and for our industry. I am very much looking forward to starting a new chapter.”

It was unclear what prompted Everson’s departure, but there has been executive shuffling at Facebook for more than a year. Facebook issued a short response on Wednesday: “We wish Carolyn the best as she moves into a new chapter. We are grateful for her contributions,” said a Facebook spokesperson in an e-mail statement.

See all of Ad Age's A-List and Creativity 2021 winners here.

Nicola Mendelsohn was named in the interim to fill Everson’s role as head of the Facebook global business group. Mendelsohn has been leader of the EMEA region for the global business group for more than eight years. Facebook said Mendelsohn was not promoted to officially take over Everson's position, at this time.

Everson’s departure is a major one, as she has been one of the most steadfast executives navigating some of Facebook’s thorniest issues, particularly when they had to do with advertising. Facebook, which generated $84.2 billion in 2020 from ad sales, has had a stormy relationship with marketers, and Everson has often been the one to reach out to the brands and ad agencies to perform damage control.

Advertising executives who have been close with Everson for years were still processing the news Wednesday afternoon. “Carolyn is well liked and will be missed, but we all know Nicola,” says one exec. “I'm not reading much into it, 10 years is a long time and people do re-assess things.”

In 2011, Everson was the driving force behind one of Facebook’s most important initiatives with advertisers by forming the Facebook Client Council. It was an invitation-only group designed to create a working relationship between the social network and brands before it even went public as a company. Everson introduced the council at 2011’s Cannes festival.

In 2016, Everson was front and center after Facebook reported that it messed up sharing metrics with advertisers, inflating certain video views. Everson appeared at Advertising Week that year to smooth it over with brands and promise better reporting. In the ensuing years, Everson stood by Facebook as it handled accusations of misusing data with the Cambridge Analytica episode, and over other social media failures around the 2016 U.S. election. 

Last year, Everson was integral to how Facebook responded to critics who mounted a boycott against the social network over concerns about hate speech and misinformation.

Everson has also worked steadily behind the scenes, talking with Facebook’s biggest advertisers about how it would fix what they perceived as long-standing credibility issues.

In an interview last August, following the brand boycott that was organized by civil rights groups, Everson talked with Ad Age about the impact. “So, my job is to be the face of Facebook to the industry, and take their feedback, get their feedback, go back into the company to ensure that we have the right actions in place, so I can go and look people in the eye that I have known for 20-plus years, and say, we’re committed and we’re on this and here’s the timeline,” Everson said at the time.

Under her leadership, Facebook has committed to work with groups like the World Federation of Advertisers and the Global Alliance for Responsible Media to improve brand-safety controls. Facebook has also tried to improve how it reports on metrics, like the ones that caused an issue in 2015 and 2016.

Facebook has opened to third-party measurement firms, so it is not seen as “grading its own homework.”

These were all initiatives that have become bigger movements within the digital ad industry. Major brands have been clamoring for guardrails in settings like Facebook News Feed.

Everson was not immediately available for comment on her plans.

See all of Ad Age's A-List and Creativity 2021 winners here.