"We want all survivors of sexual harassment, everywhere, to be heard, to be believed, and to know that accountability is possible", the letter read, noting that Time's Up wasn't just limited to helping those in Hollywood.
"The clock has run out on sexual assault, harassment and inequality in the workplace".
"Like you, there are few positions available to us and reporting any kind of harm or injustice committed against us doesn't seem like a viable option". The campaign with hashtag #timesup will also push for legislation to penalise companies that tolerate harassment and to discourage the use of nondisclosure agreements to silence victims, according to the New York Times.
Several females in the industry have donated to the legal defense fund, including the incomparable Taylor Swift, who faced her who sexual harassment trial back in August. It will be housed and administrated by the National Women's Law Center, and now has more than $13 million in donations.
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"It's very hard for us to speak righteously about the rest of anything if we haven't cleaned our own house", producer Shonda Rhimes told the Times.
On Monday, a group of women in the entertainment industry, including A-listers such as Shonda Rhimes, Reese Witherspoon, Jennifer Lawrence, Emma Stone and Natalie Portman, announced a new initiative called Time's Up, which is aimed at combating sexual harassment.
The meetings reportedly began in October, shortly after Harvey Weinstein was first accused of sexual assault.
More broadly, Time's Up says it will work to promote diversity in corporate management and help more women and men obtain legal help to hold wrongdoers accountable.
The campaign comes after a slew of allegations of sexual misconduct against Hollywood mogul Harvey Weinstein past year sparked the #MeToo campaign, with women and men using social media to talk about their experiences of harassment.