The 100 Best Workplaces for Women is a “best of the best” ranking. The winners come from a universe of companies who are certified this year by Great Place to Work® as great workplaces and have published Great Place to Work® Reviews, meaning they are serious about creating a great workplace and comfortable with transparency.

To create this list, Great Place to Work® surveys employees at these companies, who answer a detailed questionnaire considering everything from the fairness of their company’s promotions, to who has access to information and leadership, the level of support for employees’ personal lives, and the degree of inclusiveness and connection they feel with colleagues. We consider women’s experiences compared to men’s on these 58 questions in total, including an overall assessment of whether the company is a great place to work.

These survey results have a high degree of reliability in accurately reflecting employees’ experiences: In statistical terms, women’s survey results all meet a 95 percent confidence level and a margin of error of 6.5 percent or less.

The survey results are the biggest reason companies appear on this ranking, since two-thirds of each company’s score is based on women’s reports. The remaining third takes into account how well-represented women are within the workforce overall and in management and executive positions. We also gave higher scores to companies who achieved the highest level of parity between men and women in their organization – meaning, companies where not only the most women reported the company performed well on an index of fairness-related questions, but also those where just as many women had that experience as men.