Both WHO and IAP encourage using combination vaccines, wherever feasible. The phase III trial reported here was conducted to assess and compare the immunogenicity, tolerability and safety of two quadravalent vaccines, Quadrovax(®) (new vaccine), and TETRAct-Hib(®) (available in the market) in a multicentre study, in India. In all, 361 infants aged 6-8 weeks were enrolled, out of which 339 completed the study. The vaccination was done at 6-10-14 weeks following EPI/WHO recommended immunization schedule. Blood samples were collected prior to the administration of first dose and one month after the third dose. Postvaccination, geometric mean titres for each component did not differ significantly between the single dose vial and multi dose vial subgroups and among the two study groups. Adverse events observed were within the range quoted in literature. Quadrovax(®) vaccine manufactured by SIIL was found to be safe, immunogenic and non-inferior to the comparator vaccine. The quadravalent vaccine is best recommended in the second year of life when children receive their booster dose at 15-18 months. It can be given to infants during primary immunization series at 6, 10 and 14 weeks of age when Hepatitis B vaccine is given in a separate arm or to infants at 10 weeks who receive the Hepatitis B vaccine separately following the 0, 6 and 14 weeks or 0, 1 and 6 months schedule.