A Harvard Business Review research report concluded that the primary factor “keeping women under the glass ceiling” is “the absence of male advocacy.” The report found that high-performing women simply are not getting the male mentorship they need to reach the top because they are not interacting in business contexts on a one-on-one basis with the senior men in their organizations. Without such interactions, male leaders lack the familiarity, knowledge, and incentive to sponsor women and advocate for their career advancement.

This absence of cross-gender one-on-one professional interactions is due, in part, to something we can all relate to: the desire to be with people who are like us. Senior men are no different. They gravitate toward, are more comfortable with, and find more enjoyable the company of people who are like them — in this case, junior men of the same race.

Certainly, senior men’s affinity bias explains in part why the Harvard Business Review study found that 64 percent of executive men are reluctant to have one-on-one meetings with junior women. But affinity bias does not at all explain why half of junior women are equally reluctant to have such meetings with senior men.

Women’s reluctance to interact one-on-one with senior men in business settings is surely due, again in part, to concerns about inappropriate sexual advances. There is no escaping that sexual harassment in the workplace is a serious problem — think Uber, Fox News, and Silicon Valley generally.

Why the Impropriety Bias Is the Biggest Obstacle to Men Mentoring Women

But beyond women’s concern about sexual harassment and senior men’s affinity bias, there is another, even more powerful, factor at work preventing one-on-one cross-gender workplace interactions. This is the pervasive assumption among Americans that when members of the opposite sex eat, travel, and meet alone, something improper must be going on. We call this the impropriety bias, and it was probably most clearly articulated by Billy Graham in his autobiography. As he wrote in 1948, “I and a group of other Evangelicals pledged among ourselves to avoid any situation that would have even the appearance of [sexual] compromise or suspicion. From that day on, I did not travel, meet or eat alone with a woman other than my wife.”

It was revealed that former Vice President Mike Pence deals with women in accordance with what might be called the Graham Rule, refusing to have one-on-one contact with women other than his wife. When Pence’s policy was reported, there was a flurry of media attention, much of it mocking him for his prudery and depreciation of women.

The media, however, was far too quick to poke fun at Pence for his and Graham’s view of “appropriate” cross-gender contact. Their view, it turns out, mirrors precisely that of the majority of Americans. As Claire Cain Miller reported in The New York Times, 60 percent of women and 48 percent of men think it is inappropriate to have a drink with a person of the opposite sex who is not your spouse. Only slightly fewer, 53 percent of women and 45 percent of men, think having dinner under similar circumstances is inappropriate. And “nearly two-thirds [of those surveyed for The New York Times poll] say people should take extra caution around members of the opposite sex at work.”

The impropriety bias, espoused by Graham and Pence and openly supported by most Americans, results in an intense suspicion of one-on-one cross-gender business contacts. Like all gender biases, the impropriety bias is fostered by stereotypes. In this case, the notion is that men are sexually aggressive and easily seduced, and that women are provocative and sexually vulnerable.

Because of these stereotypes, affinity bias, and the reality of sexual harassment, women and men are in a very dicey situation when they can or must work one-on-one with someone of the opposite sex. Women face a clear double bind: If they accept or seek out male mentors, they risk possible hurtful gossip or worse. If they avoid male mentors, they damage their prospects for career advancement. Men don’t have it quite so bad, but they have little or nothing to gain from advocating for women given the serious negative consequences for their careers and reputations if there is suspicion of their sexual impropriety.

What Everyone Can Do to Help Women Find Male Mentors in the Workplace

Women already face serious obstacles to their career advancement because of pervasive gender bias in the workplace. The impropriety bias significantly adds to those obstacles. Yet if gender parity at all levels of business is to be our goal — and we firmly believe it must be — then women and men must find ways to deal with one another in professional contexts in the same open, transparent, and easy manner in which men now deal with other men. 

For this to become a reality, 3 things need to happen:

1. All of us need to openly and explicitly reject the Victorian prudery at the root of the impropriety bias and be willing to defend the appropriateness of one-on-one cross-gender communication and support.

2. Senior men need to mentor and advocate for the women, and not just the men, who work for them and to speak out forcefully about the importance of such advocacy for women’s career success.

3. Both women and men need to maintain “an expectation of propriety” as they deal one-on-one with the opposite sex. If that expectation proves misguided, then, of course, defenses need to go up, but unless there is actual impropriety, we need to give each other the benefit of the doubt. Such an expectation of propriety will help open the gates for many of our most talented leaders to get to the top.