Chances are you haven’t given much thought to the inner life of the garment worker—the seamstress halfway around the world who made your clothes. But nine years ago, the Gap—a retailer that relies on millions of them—took note. “These women who are sewing, they all have the same desires to grow and advance,” says Dotti Hatcher, a Global Sustainability executive at Gap (GPS). “How do we help give them the opportunity?” It launched P.A.C.E. (Personal Advancement & Career Enhancement), a 65-hour-plus life skills program for women in its supply chain. The curriculum, tailored to local context and delivered in weekly courses, covers everything from problem solving and decision-making to financial literacy. Workers claim they gain confidence. Factory owners—a sort you might expect to be unnerved by employee advancement initiatives—are happy too, reporting increased productivity and lower attrition rates. Gap, which has so far reached more than 40,000 women in 12 countries—and which pledges to reach 1 million by 2020—now offers P.AC.E. in community settings and even the factories of its competitors.

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A version of this article appears in Fortune’s September 1 issue as part of the Fortune Change the World list, our annual ranking of major companies whose business activities are having a positive social impact. Click here to see the entire package.