With the spread of immunization having stalled in many parts of the world, a wider look at its benefits is timely. In this paper, the authors discuss the value of vaccination from a broad perspective. As well as the health benefits, we examine the cost of vaccine programs and their economic impacts. Vaccination has proved a cost-effective and remarkably efficient way of improving health, and has saved millions of lives. It has the potential, however, to be more effective still, and renewed efforts are needed if the momentum is to be regained.