Fortune’s annual Best Workplaces for Women rankings, based on anonymous employee surveys, ranks McLean, Virginia-based Hilton Worldwide No. 1 on this year’s list of Best Large Workplaces for Women.

Fortune reports 52.4% of Hilton’s workforce are women, though that alone is not all the rankings are based on.

Employees answered more than 60 survey questions describing what makes their organization a great place to work, with 85% of the ranking based on what women report about how their experiences compare to men in the same workplace.

The rankings weigh areas such as employee trust, whether they feel they are able to reach their full potential, daily experiences of innovation and the effectiveness of leaders as well.

To make the list, companies need at least 20% of their nonexecutive managers to be female and at least one of their executives needs to be female too.

Fortune and partner Great Place to Work analyzed feedback from more than 5.6 million employees.

Other companies with D.C.-area headquarters that made the list of 75 large companies include Navy Federal Credit Union, at No. 25, Marriott International, at No. 26, and Capital One Financial, at No. 48.

Fortune’s 2021 Best Large Workplaces for Women, as well as rankings for the best 25 small and medium sized workplaces is available online.