This Stanford Social Innovation Review article explores businesses that more fully incorporate a for-profit component to fund a social mission than traditional nonprofit social enterprises. A primary challenge to the hybrid model is the constant tension between mission and market, where the search for more profitable markets may ultimately crowd out the very people the organization is attempting to serve. However, other challenges – and opportunities – exist. This hybrid model has gained increasing notice in the wake of the 2008 financial crisis. To date, sector growth has been modest. Nonetheless, Echoing Green, a nonprofit that supports early stage social business development, reports 50 percent of their 3,500 applicants now rely on this hybrid model, up from just 37 percent in 2006.