On April 12, a manager at a Starbucks in Philadelphia called the police because two black men were sitting in the store without having made a purchase. Video of the incident spread quickly on social media, and the company's CEO, Kevin Johnson, has apologized to the men. He's also said that Starbucks wants to change its corporate culture, beginning with a half-day of diversity training for workers at all of its U.S. stores on May 29th.

Does Diversity Training Work?

However, this kind of training is often ineffective, Harvard sociologist Dr. Frank Dobbin tells Quirks & Quarks. Discrimination is often rooted in stereotypes, which can be hard to eradicate. Studies have shown that, within days of a training session, bias is often back at its original level, Dr. Dobbin says.

When Training Backfires

Bias training can even backfire, Dr. Dobbin says. Managers sometimes resent being forced to undergo diversity training exercises, as they resist the implication that they've been discriminating in the past. The end result can be even less diversity in managerial positions, he says.

A Better Solution

A better way to reduce discriminatory behaviour in the workplace is to have people from different backgrounds working alongside each other, Dr. Dobbin says. Active recruitment of workers from minority groups is a good first step. Just being engaged in a recruitment program can help managers view the push for diversity in a more positive light. We've known for a long time "that if you put blacks and whites together, working side by side, racial animosity goes away very rapidly, and in a very dramatic way," he says.

Try out Harvard University's online implicit bias test

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