The 2017 Transformative Impact Summit, a collaboration between Bridgespan and Harvard Business School's Social Enterprise Initiative, brought together 75 nonprofit, NGO, and foundation leaders from the United States, Africa, and India to discuss strategies for achieving "impact at scale."  While there, they also heard from  a diverse set of innovators who offered short “lightning talks” designed to spark new ideas and approaches to some of the most common challenges. Below, we've collected recordings of several of those talks. Stanford Social Innovation Review has also published a set of blog posts based on the talks.