Researching routine immunization-do we know what we don't know?

There is an enormous range of research that could be undertaken to support routine immunization. However, implementation of strategic plans, rather than additional research will have the greatest impact on raising immunization coverage and preventing disease, disability, and death from vaccine-preventable diseases. The panel emphasized the importance of tying operational research to programmatic needs, with a focus on efforts to scale up proven best practices in each country, facilitating the full implementation of immunization strategies.