A legal defense fund, backed by $13 million in donations, to help less privileged women-like janitors, nurses and workers at farms, factories, restaurants and hotels-protect themselves from sexual misconduct and the fallout from reporting it.
The women said they are hoping to widen the attention being paid to Hollywood's scourge of sexual harassment and discrimination into a cultural shift.
"We remain committed to holding our own workplaces accountable, pushing for swift and effective change to make the entertainment industry a safe and equitable place for everyone", the letter reads.
Shonda Rhimes is among the women who have signed on to the "Time's Up" initiative.
The initiative, which is called "Time's Op" was announced on Monday in a full-page advert in the "New York Times".
The group are demanding legislation to penalize companies that tolerate persistent harassment and to discourage the use of nondisclosure agreements - such as those allegedly used by Weinstein - to cover up abuse.
One of the familiar faces, Reese Witherspoon, said, "We're finally hearing each other.in solidarity for every woman who doesn't feel seen, to be finally heard". The fund will be administrated by National Women's Law Center, a national women's rights legal organization. Signatories include actresses America Ferrera, Rashida Jones, Ashley Judd, Eva Longoria, Natalie Portman, Kerry Washington, and Reese Witherspoon, as well as showrunners Shonda Rhimes and Jill Soloway.
The meetings reportedly began in October, shortly after Harvey Weinstein was first accused of sexual assault.
It has already overseen the creation of a commission, announced in December, that is tasked with creating a blueprint for ending sexual harassment in show business.
As the Times reports, the group is "leaderless, run by volunteers and made up of working groups"-each of which focusing on different areas of the problem or specific populations under threat".