Serena Williams has won 23 Grand Slam singles titles — the most by any man or woman since professional tennis began in 1968 — and four Olympic gold medals.
Along the way, Williams, 38, has done more than just showcase her tennis skills. She has also been outspoken on injustices both on and off the court on topics ranging from body shaming to sexism to domestic violence and financial issues.
"You know, I take things head on. I get flak for that but it is what it is," Serena Williams tells CNBC Make It.
At the US Open final in September 2018, for example, she made headlines after challenging an umpire who accused her of cheating and then smashing her racket in frustration.
Following the incident, Williams was labeled in the media as being emotional, angry and irrational.
But to her, she was just speaking her truth at that moment. "I need to speak up. I have to or I won't be able to sleep at night," she says.
However, there is a way to get her point across, she says.
"It's really about seasoning your words with salt," Williams said, referencing a bible verse (Colossians 4:6), which means to speak with grace.
"I think everything has to be done in the appropriate way and in a timely way and to share it in the right way. And that's something that I'm still learning," Williams says.
On Tuesday, Williams announced a partnership with Secret Deodorant to support gender equality programs in sports. Procter & Gamble, the makers of Secret have pledged $1 million to support equality programs for women and girls to help them advance in all areas of sports.
"It's very important to me that I use my platform to bring attention to the many issues faced by women in sports and to call for meaningful change," Williams said in a press release.
Though Williams says gender equality has improved significantly since she started playing in the late 1990s, improvements are still needed when it comes to wages, opportunity and resources to help athletes who are mothers.
"For me, I always think about the future. I say this wasn't great but let me think about how I can help the next generation so the next person won't have to go through this," she says.
"Things are not going to be perfect in this world and this system [but] you have to use your voice when you can," Williams tells Make It.
While Williams says she is comfortable using her voice, she understands it's not for everyone.
"I don't think people should be forced to speak up if they don't want to, because they may not be comfortable. You never know what people are going through internally. I think it's really important to support each other, even if it is silent sometimes," she says.
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