In the developing world today, less than 20% of children are immunized against diphtheria, pertussis, tetanus, tuberculosis, measles, and poliomyelitis. Consequently, these diseases kill 10 children and disable 10 more each minute. To address this problem, the World Health Organization created the Expanded Programme on Immunization (EPI), with the goal of reducing morbidity and mortality by making immunization services available for all children of the world by 1990. This goal will be difficult to achieve. Information systems and immunization services themselves need to be strengthened. This goal will require commitments by the developing countries of human resources and commitments by developing and developed countries of financial support. Commitment is also needed by parents, who need to be informed that death and disability from these diseases can disappear if their children are immunized. Can these commitments be obtained? There is no choice but to try, for few appeals can be made as powerfully. The EPI cannot be permitted to fail.