Reese Witherspoon has a long history of playing strong women on screen. She was Tracy Flick in Election, Elle Woods in Legally Blonde, Cheryl in Wild, Madeline Martha Mackenzie in Big Little Lies, and she plays Mrs. Whatsit in the upcoming A Wrinkle in Time movie. Witherspoon is just as ambitious in real life. As a child, she announced plans to become the first female president of the United States (It’s not too late!), and last year, she was named Glamour’s Woman of the Year for her work creating stronger roles for women in Hollywood.

Witherspoon is on the cover of Glamour, and in the new issue, she writes about why it’s so important for women to be ambitious. Despite how frustrated she is with all the inequality in this country, Witherspoon says that when she feels like complaining, she focuses on making more opportunities for women instead. She writes:

“All we can do to create change is work hard. That’s my advice: Just do what you do well. If you’re a producer, you’ve got to produce. If you’re a writer, you’ve got to write. If you’re in corporate America, keep working hard to bust through the glass ceiling. If you want our voices to be represented in government—and I think we’re all getting behind that idea now—encourage women to run and help them with their campaigns. If you are one of those people who has that little voice in the back of her mind saying, ‘Maybe I could do [fill in the blank],’ don’t tell it to be quiet. Give it a little room to grow, and try to find an environment it can grow in.”

She urges women who are working in jobs where they don’t feel valued to seek other opportunities, and offered similar advice regarding relationships. She says, “Run away from a man who can’t handle your ambition. Run. So many men think ambition is awesome and sexy!”

Witherspoon is best known as an actress, but she also has her own production company, Pacific Standard, which produces women-centric projects like Gone Girl, Wild and Big Little Lies. That company is now a subsidiary of her new multimedia company, Hello Sunshine, which she created to tell women’s stories using movies, TV, and digital platforms. She also has her own clothing company, Draper James. Witherspoon wants the world to realize that ambition makes women awesome and sexy, and we don’t have to take her word for it—she is living proof that it’s true.