But perhaps the most common and seemingly elementary tactic -- compulsory diversity training aimed at helping people's biases or preventing discriminatory behavior -- appears to actually do more harm than good.
In the cover story of the latest issue of the Harvard Business Review, sociologists from Harvard University and Tel Aviv University explore the counterintuitive idea that some of the most common tools for improving diversity -- one of which is mandatory training -- are not just ineffective. They could be detrimental to improving the number of women and minorities in the managerial ranks.
Making people attend diversity training may seem to make sense, said one of the study's co-authors, Alexandra Kalev, in an interview: "But it doesn’t work. For decades, diversity management programs flourished with no evidence whatsoever about their effects and their success."
The article is based on a series of research papers by Kalev and Harvard's Frank Dobbin that studied nearly 830 U.S. companies. It describes how, five years after implementing compulsory diversity training for managers, companies actually saw declines in the numbers of some demographic groups -- African American women and Asian American men and women -- and no improvement among white women and other minorities.
"If someone is supposed to sit there, psychologically they will be grumpy," she said. "They will not want to engage. This is what we do as human beings -- we resist control."
The authors point to a range of past social science studies that have shown that efforts to reduce prejudice can backfire -- actually increasing bias or leading to more hostility rather than less. In another past study, white subjects who felt forced to agree with a document about bias toward blacks felt more prejudice; those who felt they could choose felt less. The pair also say that when diversity training is just focused on a certain group -- like managers or one where there's been a bias problem -- it can also have worse results. "When diversity training focuses only on managers it has this legalistic undertone," Kalev said. "You are the decision makers, therefore you have to go through driving school."
The researchers also found that other tactics often aimed at helping with diversity, such as skill tests to help prevent bias in the hiring process or grievance systems where employees can log complaints, also led to declines in the number of women and minorities in the companies' workforces over time. Managers don't like being told who they want to hire, so they often distribute tests selectively, Kalev said, while grievance systems can make managers feel threatened and retaliate. "We understand why they need to be there," Kalev said of such tools. "But we think companies need to be way more reflective about what these [practices] do for their workforce."
The researchers used a statistical analysis to examine the effect that a range of diversity efforts had on each company's makeup over time, examining both detailed surveys and data on the demographics of their workforce. By isolating factors like broader industry diversity figures, organizational culture, or the presence of a union or an affirmative action plan, they believe their research shows that some diversity tools actually hurt or help the number of women and minorities in the ranks, rather than merely being linked with each other.
Of course, diversity training programs can vary widely -- from being forced to watch outdated 1980s VHS tapes about sexual harassment to attending sophisticated new "unconscious bias" training programs. And Kalev said their research has shown that training programs that focus on multiculturalism and the business case for diversity -- rather than the legalistic reasons behind why it's being offered -- have a less negative impact. Still, she says, "even the most fascinating diversity training will be way more efficient if the crowd is sitting there voluntarily."
Indeed, that's one of the tactics their research found actually lead to more diversity among managers. Voluntary programs that let people choose whether to attend might seem futile -- most people don't think they're biased, so might not attend -- but engagement, rather than coercion, led to growth among several minority groups in Kalev's research. Diversity managers told she and Dobbin that 80 percent of people typically do attend, even when programs are voluntary. And strong representation from leaders can be one way to help encourage people to show up.
"If people in the higher ranks go, other managers might think 'I want to show my face there too,' " said Kalev. "It's like with kids: There’s a way to make them choose what you want them to choose without forcing them. The 20 to 30 percent who don’t come -- you don’t want them there. They will be grumpy and they will be toxic."
In addition to voluntary training programs, Kalev's research found that college recruitment aimed at women and minorities, as well as the addition of mentorship programs, diversity task forces and diversity managers, all led to improved diversity among managers over time. Creating a diversity task force within a company, for instance, led to a 30 percent increase in Asian men and a 23 percent increase in black women over five years.
One key difference, Kalev said, is that while "a diversity task force is something you do in-house, diversity training is a product you buy from a consulting firm." Consulting firms, she said, often use the prevention of legal trouble as a sales pitch for mandatory training programs, even without data showing their effectiveness.
Asked about how diversity managers have responded to their research, Kalev said they "tend to agree with us. They have the same inclination from their own work." And diversity consultants? "They don't like us so much -- which makes us even more assured [of] our findings."