The economic model for scaling, presented and discussed in this chapter, highlights three key players that have a role in scaling up programs: researchers, policy makers, and participants. Policy makers choose which programs to implement, with the goal of maximizing the benefit to individuals within constraints from time, available funding, and available resources. In addition to the policy makers and researchers highlighted in the economic model, chapters in this book examine the roles of program leaders, as well as funders of research and programs. In this chapter, the authors highlight key recommendations for policy makers, researchers, program leaders, and funders to support the development of scalable interventions. The threats to scaling identified in the economic model can be partially addressed through using research designs that focus on more representative research participants and implementers and more representative programs.