Managers and employees announced together in November that roughly 280 current and former Yank Sing workers had won a $4 million settlement. It was one of the biggest of its kind. The way labor advocates see it, the case ended well. But it wasn’t easy to get there.

Behind the scenes, a core group of low-wage immigrant workers who speak little English waged a dogged campaign for almost a year and a half. They feared that their activism might get them fired, but gradually they organized fellow workers who had plenty of reasons to back down.

Li Xiu Zhen was one of the leaders of the worker campaign.

Li is a 61-year-old immigrant from southern China, the birthplace of dim sum. Her workdays are spent frying sesame balls, wrapping wontons and peeling shrimp. She’s been making dim sum at Yank Sing for six years, and she earns a little more than minimum wage. For most of those years, she typically put in 11- or 12-hour days. But until recently, her paycheck would show that she’d worked only eight hours.

That is one of the labor violations that the California Labor Commissioner's office found in its investigation of Yank Sing. Attorney David Balter said the agency found that tips were being taken by managers and people were being forced to work off the clock.

“People need to be paid,” Balter said. “That’s pretty obvious. People need to be paid for hours they’re working.”

Labor advocates say wage theft is rampant and cuts across many industries. Haeyoung Yoon, with the National Employment Law Project, said three out of four low-wage workers in the U.S. weren’t properly paid for overtime in 2008. She called the problem epidemic.

“We say this is one of the defining trends of the 21st century labor market,” Yoon said.

Not everyone agrees that wage theft is a huge problem. Janna Haynes is a spokeswoman for the California Restaurant Association, which represents restaurant owners.

Advocates say workers in this situation often just keep their heads down.

“I do not think that wage theft is widespread,” Haynes said. “I think there are some isolated incidents of it. I don’t like it. The California Restaurant Association doesn’t like it, and we don’t have any tolerance for that behavior from employers.”

Yet in San Francisco, half of restaurant workers in Chinatown said they were being paid less than the minimum wage in 2010, according to a survey by the Chinese Progressive Association.

Advocates say workers in this situation often just keep their heads down.

At first, Li had worried she might be fired if she complained. But she knew her co-workers were increasingly frustrated over how they were treated at Yank Sing. She doesn’t speak any English, but she decided it was time to speak up.

In an earlier restaurant job, she had won back pay. She thought it could also be done at Yank Sing. Her co-workers were nervous. So Li became one of the organizers who gave them the confidence to join the campaign.

“After work, we would go to their homes, and talk openly one on one,” Li said. “Sometimes we’d be there until 11 or 12 at night.”

Those late-night meetings built momentum.

And remarkably, Yank Sing’s management was willing to listen when the workers came forward with their complaint. The restaurant is a family business owned by Henry and Judy Chan.

“I think our ownership was genuinely shocked when they found out and were made aware of these issues,” said the restaurant’s director of operations, Jonathan Glick. He joined the management team after the owners learned of the problem. He said the Chans have replaced three-fourths of the old management team.

After negotiations over a year and a half, the Chans agreed to pay four years worth of back wages.

Workers now get proper breaks, and use timesheets to track their hours. And they have fully paid health insurance. Li says she can now leave work in time to enjoy simple things, like buying groceries to cook her family’s evening meal. She says it’s made a huge difference.

“Of course, things are much more relaxed, much happier now,” said Li.

Yoon at the National Employment Law Project says the Yank Sing victory is part of a movement that’s been growing nationally over the past couple of years.

“Fast-food workers, retail workers, restaurant workers, domestic workers (are) really coming forward to demand better wages, better working conditions,” Yoon said.

Shaw San Liu is with the San Francisco-based Chinese Progressive Association. Throughout the campaign, her organization and the Asian Law Caucus helped the Yank Sing workers understand their rights, organize as a group and take their requests to management.

Liu said she’s proud to see what benefits these immigrant workers have won.

“All of these things, they’re pretty unheard of, to happen in this industry," Liu said. "We think it sets a precedent for other restaurants.”

Now Li, the dim sum cook, hopes Yank Sing will be an example to others to take up the fight against wage theft.

“Hopefully everyone will organize more people, and be better informed so they can get our kind of pay and have better lives,” Li said.

She said the campaign changed her. She learned she could sit at a negotiating table with managers who she was once nervous just to talk to.

And she’s keeping up her fight for workers rights, by helping organize workers at other restaurants to speak up against abuse.

Note: This article has been changed to reflect the fact that the state agency that enforces labor laws is the Division of Labor Standards Enforcement, which is part of the Department of Industrial Relations. We regret the error.