Tina Tchen, a lawyer and former chief of staff to former First Lady Michelle Obama, was appointed president and CEO of Time’s Up.

Time’s Up, an advocacy group formed as the #MeToo movement roiled Hollywood, aims to advocate for safer and more equitable work conditions for women across multiple industries. Tchen co-founded the organization’s legal defense fund, a resource that has since raised over $24 million for women who experienced sexual harassment at work.

Tchen appeared on CBS This Morning shortly after the news was announced Monday morning, saying she “couldn’t be more thrilled” to start.

“I’ve been living these issues my life,” Tchen told Gayle King and co-anchors on CBS This Morning. “I’ve been a single working mom my entire career, working in places like law firms and the White House so I’ve seen the issues that women confront in workplaces. And I’ve been working on gender equity issues for over three decades.”

Tchen says her biggest challenge will be changing companies’ workplace culture. “It’s been three decades since the Supreme Court outlawed sexual harassment, and yet here we are today,” she said.

Last March, Tchen was appointed as chair of the Recording Academy’s task force for inclusion, an effort to examine diversity within the Academy and the music community; a rep for the Academy tells Variety that Tchen will remain in that role. She was previously an assistant to President Barack Obama and served as executive director of the White House Council on Women and Girls.

A number of celebrity supporters, including Shonda Rhimes, Reese Witherspoon, Eva Longoria, Natalie Portman, Meryl Streep and Brie Larson, helped launch the Time’s Up initiative. Time’s Up was founded two years ago amid fallout over sexual harassment allegations against moguls like Harvey Weinstein, Kevin Spacey, Matt Lauer and Brett Ratner.

“Tina knows the power and opportunity of TIme’s Up as a valuable ally helping bring this organization to life early on,” Rhimes, a principal founder of the organization, said in a statement. “Tina’s talent and unique skill set perfectly suit her for this role and time, and will help ensure our continued progress towards meaningful change.”

Adds Streep, another principle founder, “Tina Tchen will bring her formidable energy, legal chops, and famously irrepressible optimism and compassion to this work — we are so lucky she has picked up the banner. Time’s Up will march on under her sharp, focused leadership. I salute her and thank her.”

Former president and CEO Lisa Borders resigned from her post in February after three months on the job when her adult son was accused of sexual harassment. Borders was the first president and CEO of the organization. Tchen will take over on Nov. 1 from interim CEO Rebecca Goldman, who served as interim CEO since February. Goldman will continue as COO.