This paper describes the steps that might be used in assessing the economic justification for using vaccination to control animal disease, and the way that vaccination is financed and administered. It describes decisions that have been taken with respect to preserving international trade, and issues related to protection of livelihoods. Regardless of the motivation for vaccination, its costs can usually be shared between the public and private sectors. Cost-effective vaccination requires methods of delivery to be adapted to livestock production systems. The paper concludes by suggesting questions around the use of vaccination that would merit further economic analysis.