Despite growing interest in evidence-informed policy making, understanding of how to scale-up effective programs is still limited. Successfully scaling up an evidence-informed program or intervention requires: a deep understanding of both global evidence and the specific local context and systems, a policy window where change is possible, political will to change the status quo, adequate funding resources, and capacity to monitor and implement the program well. Because no single organization’s mandate covers all of these conditions, collaborations between policy makers, researchers, practitioners, funders, and evidence-to-policy organizations can ensure that these scale-up conditions are met. In this chapter, we draw on the Abdul Latif Jameel Poverty Action Lab’s (J-PAL) many years of experience in building scale-up collaborations to share key lessons we have learned about how to build scaling collaborations that combine the complementary skills and expertise each partner brings. The four key lessons are to: (a) invest in long-term partnerships and develop the resources to respond to policy windows in real time; (b) use several complementary types of data and evidence to inform every scaling effort; (c) help institutionalize a broader culture of evidence-informed policy making that goes beyond individual programs; and (d) leverage evidence-to-policy organizations that can play a critical role in bringing different stakeholders together to make change happen.