The benefits of vaccination are, in general, recognized. For some diseases these benefits are obvious. When starting or evaluating new vaccination programmes, a more critical approach is needed. Before starting vaccination against measles and rubella in Finland a cost-benefit study was performed. According to those studies the net benefits of each vaccination would be ca. 100 million Finnish marks in 25-30 years. Those benefits not measurable in money value of human life, decrease of suffering, etc., were not included. For the purpose of formulating the national influenza vaccination policy a similar study was performed on influenza. The method used before seemed to be less suitable, however, with certain assumptions the vaccinations against influenza proved to be profitable.