A new study from Harvard Kennedy School is shining a light on just how deep the disparities go when it comes to race, gender, and workplace advancement. Researchers Elizabeth Linos, Sanaz Mobasseri, and Nina Roussille set out to understand how the racial makeup of a team impacts long-term career outcomes. What they found was deeply concerning. Black women who begin their careers working with more white colleagues are significantly more likely to leave their jobs and less likely to be promoted.
At first glance, that might sound surprising. Aren’t diverse teams supposed to be a good thing? Isn’t inclusion the goal? But the reality is more complicated, especially for Black women.
The Hidden Costs of Being “The Only”
The research analyzed data from over 9,000 new hires at a major professional services firm between 2014 and 2020. It tracked factors like performance reviews, time spent on projects, promotions, and turnover. The study uncovered a pattern that the more white colleagues a Black woman worked with at the start of her job, the more likely she was to be labeled a low performer and the less likely she was to rise through the ranks.
When Black women started their careers on teams with about 20 percent more white coworkers, they were 16 percent more likely to leave the company and 12 percent less likely to be promoted. These trends didn’t hold for other groups, not even other women of color. This effect was unique to Black women, underscoring how their experiences at work can be shaped by a very specific form of racialized and gendered bias.
It’s Not Just About Numbers, It’s About Systems
This study doesn’t just point to interpersonal issues or implicit bias. It uncovers systemic patterns that start from day one. One key factor is performance evaluations. Black women with more white coworkers early in their careers were more frequently marked as low performers. They also logged more training hours, raising questions about access to support, mentorship, and opportunities for high-impact work.
It’s not enough to recruit Black women into top firms, organizations must also examine how they’re being treated once they arrive.
Intersectionality at Work
This research adds to what many Black women have long known for decades: Black women’s experiences in the workplace cannot be understood by looking at race or gender in isolation. Instead, they must be viewed through the lens of intersectionality or the overlapping systems of oppression that create unique barriers for Black women.
In many firms, white-dominated teams and cultures can lead to isolation, exclusion from key networks, or a lack of sponsorship. These are all factors that quietly influence who gets ahead and who gets left behind. The presence of white coworkers isn’t inherently harmful, but the structure of workplace practices often fail to account for how bias and inequality show up in practice.
What Needs to Change
For companies that are serious about equity, and not just diversity, this research is a call to action.
It’s not enough to focus on recruitment strategies and bringing in more “diverse talent.” Leaders must dig deeper into their internal processes. Who is getting staffed on important projects? Who is being mentored? How are performance reviews conducted, and who is evaluating whom? Equity is about making sure that success isn’t determined by proximity to whiteness, but by the actual quality of someone’s work.
Organizations often blame the “pipeline problem” which is the idea that there aren’t enough qualified candidates from underrepresented groups in the talent pool to achieve diversity goals. However, they must understand that it’s a myth when retention is this closely tied to workplace dynamics. If Black women are being pushed out or stalled in their careers due to avoidable structural barriers, then the problem isn’t with the talent, it’s with the system.
For Black women, career success should not come at the cost of constantly navigating racially charged dynamics or proving themselves in environments where they’re routinely underestimated. Along with statistics, this study is a mirror reflecting what many have experienced but haven’t always had the data to prove.