Patients and citizens want more and better healthcare, and want to pay less for it. One way rapidly to respond to these demands is to spread proven or promising improvements in treatments or service delivery models. However, there is little research from high-income countries about effective ways to spread these improvements. In international health there is more experience and knowledge of scale-up, more variety in research approaches used to study the subject, and fewer resources and infrastructure for scaling-up improvements across a nation. This paper draws on reviews of research and experience in international health to contribute to conceptual and empirical knowledge as well as to practical strategies. It describes and illustrates three approaches: hierarchical control, participatory adaptation and facilitated evolution. It presents lessons from international health which could be of use to those studying, choosing, planning and progressing strategies to increase the uptake of proven or promising interventions to health services in high-income countries.