Reese Witherspoon, Shonda Rhimes and Jennifer Aniston are among hundreds of Hollywood women who have formed an anti-harassment coalition called Time’s Up.
The initiative was launched on Monday with an open letter vowing support for women in the entertainment business and beyond, from janitors to health care workers.
Time's Up will include a legal defence fund and will advocate for legislation combating workplace harassment.
Time's Up also is backing the movement for women to wear black, in solidarity with those who have been sexually harassed, at Sunday's Golden Globes ceremony.
Donators to Time's Up defence fund include Meryl Streep and Taylor Swift and Viola Davis, as well as J.J. Abrams.
Dozens of men have faced harassment and assault allegations in recent months, including Harvey Weinstein, Charlie Rose and Kevin Spacey.