Twenty four subjects were simultaneously administered DT toxoids, OPV and HBV vaccines at the age of 3, 4-5 and 11 months and then followed up for 2 and 4 years in order to evaluate the duration of the immune response and the need and the timing of HBV revaccination. A fall in anti-HBs titre below 10 mIU/ml was observed at the follow up in 4/24 (16.7%) of the subjects. In other 5 children (20.8%) anti-HBs titre was found to be just above 10 mIU/ml. This would suggest that a revaccination is indicated and it could be performed at the age of 5-6 years when children enter school. This schedule is simple, effective and money saving since it reduces the cost/benefit ratio and the number of visits for immunisations, and it is expected to improve the compliance for the vaccination.