OBJECTIVES: Since the introduction of conjugate vaccines against Haemophilus influenza type b (Hib) and Streptococcus pneumonia, Neisseria meningitis is the leading cause of infant bacterial meningitis.  HibMenCY is a new combination vaccine being developed for protection against meningococcal groups C and Y (MenCY) and Hib.  This analysis compared the cost-effectiveness of a four dose HibMenCY vaccination strategy (2, 4, 6 and 12 months) to Hib vaccination (2, 4, 6 and 12 months) and to no Hib or MenCY vaccination from a public health perspective. METHODS: A Markov model was used to simulate lifetime events, predicting the likelihood of disease with and without specific vaccinations.  Costs and health consequences were built into the model to allow the prediction of lifetime costs and quality-adjusted life years (QALYs).  The model was populated with published data throughout, and one-way sensitivity analyses were undertaken when there was uncertainty about key parameter values.  A discount rate of 3% annually was applied.     RESULTS: For HibMenCY vaccination relative to Hib alone, 13 additional cases per 100,000 treated patients would be prevented, resulting in an additional 104 QALYS saved.  The additional HibMenCY vaccine program cost over Hib alone was $6.61M resulting in a cost/QALY of $63,701.  For HibMenCY vaccination relative to no Hib or MenCY vaccination, 61 cases of meningitis were prevented per 100,000 treated patients, resulting in an additional 467 QALYS saved.  The additional HibMenCY vaccine program cost was $3.14M resulting in a cost/QALY of $6738. CONCLUSIONS: When accounting for the ability of the HibMenCY vaccine to prevent infection from both pathogens this intervention is estimated to be highly cost-effective.  If only the incremental benefit of MenCY is considered, the intervention would result in a better cost/QALY than that reported for several widely implemented vaccine strategies.  Thus infant HibMenCY vaccination is expected to be a cost-effective strategy that provides substantial health benefits.