This study examines the potential clinical and economic benefits for adults arising from paediatric pneumococcal vaccination in the UK. A UK birth cohort model with a 10-year horizon and using a primary 4-dose paediatric 7-valent pneumococcal conjugate vaccine (PCV) schedule was populated with 1999 morbidity and mortality data scaled up to the UK population. Herd immunity effects on adult pneumococcal hospital-treated pneumonia, meningitis and septicaemia, but not on community-treated pneumonia, were calculated using the lower end of the confidence intervals published for the effects in the US. Universal paediatric pneumococcal immunisation would prevent 1168 deaths (1141 adults) and 7147 cases (1791 adults constituted by 32 meningitis, 37 septicaemia and 1722 pneumonia) of serious pneumococcal infection (meningitis, septicaemia, pneumonia) with a resultant direct (payor) cost per life year gained of 4360 pounds. The 7-valent PCV appears to be highly cost effective.