Who’s stifling women’s progress in the business world? Married men with stay-at-home wives.

A study of 718 married men, co-conducted by NYU, UNC Chapel Hill and the University of Utah found that men with wives who do not work outside the home tend to view female coworkers “unfavourably.”

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These men tend to view companies with a large percentage of female staff members as poorly run, and more frequently deny promotions to qualified women.

In addition, these men are often in management positions, with direct control over hiring and promotion practices.

The researchers suggest these men are unlikely to respond to diversity training.

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Instead, they say the only solution is for companies to lay down the law with management. They should enact diversity targets and hold managers responsible for meeting them.

“We believe that the posture of these men embedded in traditional and neo-traditional marriages is unlikely to change dramatically until the structure of their marriages changes, an exceedingly improbable event on a large scale. Thus, we do not see that this pocket of resistance to the gender revolution will fade away,” says the study.

This isn’t about reaching a quota, add the researchers. If the attitude of this demographic won’t change, the first step is to have others recognize this inherent bias.

The study suggests management must assign accountability for diversity goals, define means to achieve those goals and evaluate progress. Then, it must appoint full-time staff responsible for making progress on this issue.

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