Sixty-two percent of millennials have considered starting their own businesses, and 72 percent think startups are “essential for new innovation and jobs,” according to The Millennial Economy (PDF). Yet the trend doesn’t end here. A 2015 Nielsen study found over ¾ millennials are willing to pay more for sustainable goods. As a generation, millennials also disproportionately seek purpose from their employment, in addition to a high salary. So it should come as no surprise that social impact startups are proliferating. But what drives these people? How sustainable are their business models? And how can they create a sustained competitive advantage?