FORTUNE -- Let's suppose you're female and puzzled by why you keep getting passed over for promotion -- despite having qualifications equal to, or maybe even better than, your male peers'. Here's a factor you probably haven't considered: If your boss is a married man, what does his wife do for a living? If she's a stay-at-home spouse, he is less likely to see you as a serious contender in the workplace than if she has a career of her own outside the home.
At least, that is the conclusion of a study, based on six years of research covering 1,200 men in the U.S. and Britain, led by management professor Sreedhari Desai. Male managers whose wives are homemakers are "a pocket of resistance to the gender revolution in the workplace," says Desai, who teaches at the Kenan-Flagler Business School at the University of North Carolina and at Harvard.
In five separate research projects, she says, "We found that employed husbands in traditional marriages, compared to those in modern marriages, tend to view the presence of women at work unfavorably -- and, more frequently, to deny qualified female employees opportunities for promotion."
Why is that? A big part of the reason is that everyone's "home environments can shape the way we behave at work," the study notes. "People are daily 'border crossers' between the domains of work and family," and leaving one's home life entirely behind at the office door requires a conscious effort.
"The men we studied were all nice guys who really believe that they are capable of seeing female colleagues as equals. They were not deliberately holding women back," Desai points out. "Rather, in the vast majority of cases, they were basing their decisions on unconscious biases they didn't realize they had."
In one experiment, 232 married male managers were asked to evaluate two competing MBA candidates and told that one of the two would receive a full salary and tuition reimbursement during B-school and a promotion to vice president afterward. The two (fictional) candidates were identical in every way, with "exemplary experience and award-winning leadership capabilities," the study says. More
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