Sandra Seville-Jones, who served as a firmwide leader at Munger, Tolles & Olson for the past decade, died Saturday due to complications from surgery. She was 58.

Seville-Jones joined Munger Tolles as a corporate attorney in 1986. She was elected as a co-managing partner of the firm in 2008 and in that position was a leader in the firm's expansion efforts, including the opening of a Washington, D.C., office in 2016.

In a recent leadership transition, Seville-Jones' longtime co-managing partner Brad Brian moved into the newly created position of firm chair, while she remained in her position with two newly elected co-managing partners, Malcolm Heinicke and Hailyn Chen.

“It was a shock. This came as a complete shock to us,” Heinicke said in an interview Monday.

Heinicke, who has known Seville-Jones since he joined the firm as a summer associate in 1996, added, “one of the reasons that the loss is so difficult to us today is that all of us have lost a leader, but a remarkably high number of people at the firm have also lost a dear friend.”

Heinicke said the firm has convened meetings to inform attorneys and clients of Seville-Jones' passing. But in the long term, he said, Munger Tolles' attorneys are  going to cope with the loss by “celebrating Sandra's life and legacy.”

In her practice, Seville-Jones specialized in corporate, business and securities law for clients in the energy, entertainment, gaming and manufacturing industries. Some of her clients included Oaktree Capital Management, The Yucaipa Cos. LLC, Universal Music Group and Cannery Casino Resorts, according to her biography on Munger Tolles' website.

Seville-Jones was the firm's second female managing partner in the last decade and an advocate for diversity in the legal profession. She served as co-chair of the Los Angeles Metropolitan Debate Commission, which is affiliated with the National Association of Urban Debate Leagues, and was a member of the Leadership Council on Legal Diversity. Seville-Jones also frequently spoke at conferences focused on women in law.

Within her community, Seville-Jones formerly chaired the planning commission of the City of Manhattan Beach and served on the board of directors of the Los Angeles Chamber of Commerce. She was also on the board of Hope Street Friends, a child care center founded by Munger Tolles under her leadership, which is located across the street from the firm's office in downtown Los Angeles.

“This is an enormous loss for our firm, our clients and the entire legal profession,” name partner Ron Olson said in a statement. “Sandra was a close friend and colleague, a beloved firm leader, a champion of diversity and junior lawyers, and a great legal mind. She owned the values our firm most cherishes and enhanced them every day she was with us. Our firm is shocked and deeply saddened by Sandra's passing, and our thoughts are with her family.”