Can the world respond to the demands of the Children's Vaccine Initiative (CVI) to produce large quantities of affordable vaccines that have never been manufactured previously? Vaccines for the world's birth cohort of 150 million will continue to be produced in the countries that use the greatest part of the global vaccine supply. Thus, the CVI will rely on increased self sufficiency in vaccine production in the developing world and “shared development” of new and improved vaccines. The CVI's goal is to direct product development to meet the needs of immunization programs, but it must not neglect production. Thus, from the start, investment at the front end of the development and production sequence requires attention to the ultimate production capacity.