Over the last month more than 1,000 current and former staffers with the aid group Doctors Without Borders have signed a letter with an explosive accusation: The vaunted organization, they say, is built on a mindset of "white supremacy" that perpetuates "racism by our staff, in our policies, in our hiring practices, in our workplace culture, and through the imposition of dehumanising 'humanitarian' programmes by a privileged, white minority workforce."

Among the signatories is Margaret Ngunang, a clinical social worker whose experience offers a window into why the grassroots campaign has become so impassioned.

Ngunang, who is originally from Cameroon, joined Doctors Without Borders just three years ago after a long career in the U.S. She says she was inspired by what she'd heard about the group from her daughter, a pharmacist already working with Doctors Without Borders. Its 65,000 members provide critical care to people in some of the most desperate and dangerous places in the world. In 1999 the group was awarded the Nobel Prize for peace.

"I thought it was a great organization given the work that they were doing in countries that have experienced war and famine," Ngunang says.

The possibility that she'd face racial discrimination from them? "It did not cross my mind at all," says Ngunang.

But Ngunang says the microaggressions began literally the moment she reached her first posting — a hospital run by the aid group in South Sudan.

Suitcases still in hand, Ngunang and another new arrival — also an African immigrant based in the U.S. — walked into the office of a top official:

"A white female, talking to two people. And when we said hello to this woman, she ignored us. You know, she turned, looked at us and continued talking."

Ngunang told herself that maybe this woman was just very busy — or an unusually rude person.

But over the following weeks, again and again Ngunang would notice white staffers treating white colleagues warmly while ignoring "people with my skin tone, people with my accent. It was this sense of being invisible because you're black."

When many of her white colleagues did notice her, Ngunang adds, it was often to second-guess her judgement and decisions. "You have everything that you do being put under the microscope," she recalls. "Everything that you do is questioned."

But Ngunang says the situation was far worse for local South Sudanese staff. For them a job with Doctors Without Borders was too precious to risk complaining about any problems — even when white staffers would talk down to them and berate them.

"For me," says Ngunang, "it was just very traumatizing to hear that and see that because [as someone who comes] from Cameroon, it brought back the colonial mentality."

Christos Christou is president of the international board of Doctors Without Borders.

In an interview with NPR about the letter, he questioned how widespread incidents of outright racism are across the organization's dozens of missions.

But he says there is no question the organization is built on a problematic model. "It's this idea of the white savior — the white doctor going and providing assistance to the people in Africa and especially to little African kids."

Christou says it's time for a total revamp:

"Being clearly anti-racist in this organization is not just about dismantling and overcoming all these barriers that may have been created over all these years," he says. "It's about rethinking the humanitarian model: The whole way of distributing the decision-making power and also the resources."

As a start, on Thursday he is convening a meeting of the international board to vote on a range of measures — including setting metrics for progress that will be regularly monitored.

But how much of this talk will translate into a new reality on the ground?

Africa Stewart is the president of Doctors Without Borders' U.S. board. She points to her own election back in 2017 as a sign of the appetite for change. Consider, she notes, who raised her:

"A surgical scrub tech, my mom — who could not go to nursing school. A Black Panther dad, [who] named [me] Africa," says Stewart, laughing. "I mean, was I not born for this?"

And she says she's part of a wave of more diverse leaders. The U.S. board of 13 members is now majority women, with two other Black members and a Mexican American.

Similarly, over the last decade the share of program leadership positions throughout Doctors Without Borders that are filled by people from the global south — as opposed to Europeans and Americans — has increased from 24% to 46%.

But Stewart also notes that various measures that she and others have pushed in the past several years are taking a long time to implement — including a plan adopted by the international board to reduce the pay gap between international staff and local staff.

"It feels like we're part of the solution. But it also feels like, 'Well, damn it. How long does it take to wear down a mountain?' "

As for Margaret Ngunang, she says when she returned from South Sudan, she confronted her daughter about all the racism she'd witnessed there.

"I said, 'Why didn't you tell me about that part of it?' My daughter laughed and said, 'Then you wouldn't have gone.' She just really believes in the mission of [Doctors Without Borders]."

On reflection, Ngunang says she still does too.

"That's the the reason I'm doing what I'm doing now," she says. "Is it going to make a change? Maybe not. But at least I will know that I added my voice."

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