Combination vaccines have been used for many years in the USA as part of the primary infant immunization series. However, the current program still requires up to 24 injections by 18 months of age. The Advisory Committee on Immunization Practices in the USA recommends the use of combination vaccines whenever possible. A combination vaccine was recently licensed in the USA for the prevention of diphtheria, tetanus, pertussis, polio and Haemophilus influenzae type b (DTaP-IPV/Hib). This product has been used exclusively for childhood immunizations in Canada for the last decade and shown to be safe and effective as part of a primary infant series and toddler booster immunization program. This article summarizes the available safety, immunogenicity and effectiveness data of this combination vaccine and provides a brief review of future trends in combination vaccine use.