The celebrities stopped at E!'s Glambot and talked about what the movement means to them.
"Well, I love that all of the women are wearing black together," Klum said, donning her own symbol of solidarity. "We're all sticking together, and I'm loving it. Girl power!"
Waithe also voiced her support and said she was "honored" to take part in the movement.
"I'm so honored to be nominated tonight with my cast from Master's of None, and I'm honored to be wearing black with all these amazing people because it's all about Time's Up: Time's Up on sexual harassment, racism, homophobia, transphobia—any sort of abuse in the workplace, it's done; it's dead," she said. "We're wearing black. We're at the funeral procession."
Echoing the stars' sentiments, Rae said she was "so excited to rally around with my fellow sisters and my fellow women to make a change."
"Time is up, and I'm happy to make an impact," the Insecure star, who was nominated for Best Actress in a TV Series in the Comedy category, said. "Bye, old Hollywood! You're dead."
Ann Dowd, who was nominated for Best Supporting Actress in a Series, Limited-Series or TV Movie for her work in The Handmaid's Tale, also said she was "happy to stand in solidarity."
Watch the video to hear the stars talk about the movement.
Time's Up is a movement that promotes equality and safety in the workplace.
Join the Movement: Click here to donate to the Time's Up Legal Defense Fund.
For complete Golden Globes coverage, watch E! News Monday at 7 p.m. and 11 p.m.