The risk of tetanus is universal, but it depends on numerous factors (socio-economic, environmental and biological) which combine to determine the force of infection. Tetanus is a murderous and costly disease. Its morbidity has greatly regressed in industrialized countries (less than 1 case per 100,000, involving mainly aged persons). On the contrary, developing countries are still severely affected (10 to 50 cases per 100,000, involving mainly neonates and children). Tetanus vaccine is one of the most effective, best tolerated and least expensive vaccines. Vaccination is the main weapon for starting disease control in developing countries, and the only way of eradicating tetanus in developed countries. Whatever the socio-economic level may be, some evaluations show that immunization cost is approximately equal to avoided treatment and seroprevention expenditures. The essential benefit of vaccination is the prevention of death, suffering and disability.