The World Health Organization Patient Safety Programme and the Harvard School of Public Health commissioned the United States Agency for International Development’s Health Care Improvement Project (HCI) to present its understanding of and experience with the effective adoption of simple, high-impact interventions, such as the surgical checklist. All too often in health care, evidence-based interventions that have been shown to produce superior results in certain locations do not spread to other sites. Therefore, practitioners of health care improvement have broadened their focus to not only develop superior models of care but also to take such models to larger scale by focusing on intentional spread, to more rapidly meet the needs of large numbers of patients.  Such spread requires making changes in the organization of care delivery, policies, resources, and other factors that will influence the uptake of the superior model. 

In planning to spread an evidence-based intervention, we must consider three key questions: 1) What are we trying to spread?  2) To whom do we want to spread it, and by when? and 3) How will we spread it?  This paper lays out a practical framework for spread that addresses these three questions and then discusses several illustrative approaches for spread and lessons learned from applying them.  The paper concludes with lessons learned from large-scale spread that can inform the spread of the surgical checklist and other simple, high-impact interventions.