Ann O’Leary (left) with Gov.-elect Gavin Newsom and his wife, Jennifer Siebel Newsom.

In his first major appointment since voters elected him California’s next governor, Gavin Newsom on Friday named Boies Schiller Flexner partner Ann O’Leary his chief of staff.

O’Leary previously held positions as a senior economic policy fellow at the Center for American Progress, a progressive think-tank, and as a lecturer in social policy and health law at the University of California, Berkeley, School of Law. She also served on the White House Domestic Policy Council under President Bill Clinton and worked as a deputy city attorney in San Francisco.

“Smart move by the governor-elect,” Democratic strategist and attorney Nathan Ballard wrote on Twitter. “Ann O’Leary is brilliant and hardworking, with a keen mind for policy and politics.”

O’Leary will also lead Newsom’s transition team.

The former senior policy adviser to Democratic presidential nominee Hillary Clinton, O’Leary joined Boies Schiller’s Palo Alto office in 2017. A policy wonk on family and children’s issues, her work at the firm has focused on regulatory and government affairs consulting for tech-company clients.

“She knows how policy & politics can be played to help people reach their higher angels. Know her as a long time friend; a great mom; leadership in national/CA politics; & private sector work, including @Airbnb,” Chris Lehane, a longtime political consultant and current head of global policy, said Friday on Twitter.

O’Leary was part of a Boies Schiller team hired earlier this year to investigate claims of a “toxic” workplace environment at the Mountain View-based Silicon Valley Community Foundation. Earlier this year, she represented a group of administrative law professors in an amicus brief in the Ninth Circuit backing San Francisco and Santa Clara counties’ policies limiting cooperation with federal immigration enforcement.

“I have known and worked with Ann for almost twenty years,” Boies Schiller partner Karen Dunn said in an email. “She is a brilliant strategist, counselor and someone who gets things done—all while being kind and respectful to all. She is a unicorn and I congratulate the new governor on finding her.”

O’Leary is the ex-wife of Associate Justice Goodwin Liu of the California Supreme Court.

Newsom on Friday also named Ana Matosantos cabinet secretary. Matosantos served previous stints as finance director for both Gov. Jerry Brown and Gov. Arnold Schwarzenegger.

Newsom has launched a transition website that solicits applications for administration jobs and asks visitors to rank policy priorities.

Newsom will be sworn into office on Jan. 7.