Yesterday, hundreds of very famous women simply disappeared.

One moment they were there, and the next they were gone.

In New York, International Women’s Day was celebrated by removing women from every advertisement, magazine cover and billboard in the town. They all disappeared, they simply weren’t there.

Why? Because despite the achievements in women’s rights made in the past 20 years, women still are “not there” yet. And some seriously powerful women decided to show the world what it would look like if we simply disappeared.

The #NotThere campaign was launched by The Clinton Foundation and website Refinery29.

Although it’s a U.S campaign, the story translates across nearly every country world-wide, as does the point that women still aren’t able to participate in society in a full and equal way.

Read more: 15 things that’ll happen before the gender pay gap closes.

It’s also attracted major star power, with the likes of Amy Poehler, Cameron Diaz and Sienna Miller appearing in the official campaign TV advertisement.

Chelsea Clinton said she hoped to grab people’s attention so they start to question “Well, why aren’t women there?”

“And then maybe they start to question other places in their lives where women are not as present as men. Whether that’s in their work environment or the entertainment that they consume or the news that they watch or when they think about the leaders of corporate America or political America. Just really starting to question, ‘Wait, why are there not more women…in every part of our lives?'”, she told Refinery29.

The campaign coincided with International Women’s Day but also marked 20 years since Hilary Clinton spoke on women’s rights at UN conference in Beijing.

It also comes as The Clinton Foundation released the No Ceilings report, which looks into female representation around the world.

“Sometimes there’s a shame attached to feeling that they are held back by the ceilings. So, we want to say, ‘no, there’s no shame, there are still very real ceilings, we have made progress but we still have a long way to go,’” Chelsea said, according to Refinery29.

The campaign also encourages women to blank out their Twitter and Facebook display pictures, to continue showing the world what it would look like if we all simply weren’t here.