“When someone from a dominant identity group intervenes, they’re perceived as more knowledgeable, more persuasive, and less biased than if the exact same comment was made by a member of a marginalized group,” said NiCole Buchanan, PhD, a professor of psychology at Michigan State University who leads workshops on reducing harassment and bias. “That really puts the onus on privileged people to step in as allies if they are committed to change.”

But responding effectively to microaggressions takes practice, and people often don’t speak up because they’re afraid of causing more harm or aren’t sure what to say, said psychologist Nicole Jacobs, PhD, associate dean of diversity and inclusion at the University of Nevada, Reno, School of Medicine.

So, how can you intervene when you see a friend, colleague, or stranger targeted by a microaggression because of their race, gender, sexual orientation, nationality, age, weight, or any other aspect of their intersectional, social, or personal identity? Here’s advice from psychologists—informed by research on intergroup relations, motivational interviewing, empathy, mindfulness, and perspective-taking—on how to move from being a passive witness to an active ally.