Bold thinking is most often seen at the margins. Organizations with small staffs and lean budgets, unweighted by habit and committed to impact, are approaching familiar problems in unfamiliar ways. They are testing new ideas to bring health care that last mile, finding creative ways to support small farmers, adapting cost-saving techniques from low-resource settings, and growing leaders from the ground up. As nimble as they are innovative, these social entrepreneurs are teaching their more established colleagues how to make lasting change. What can we learn from organizations who do things differently? How are they bringing value into the mainstream?