In Canada, publicly funded immunization programs are a provincial/territorial responsibility. In the province of Quebec, much effort has been devoted to optimize the acceptability, effectiveness and cost-effectiveness of publicly funded immunization programs for children during the last 20 years. The aim of this article is to describe how programs are planned, implemented and evaluated and to identify key factors that contribute to the success of this enterprise. A comprehensive framework was developed for the evaluation of new vaccines and new programs in a societal perspective. It is used by the Quebec Immunization Committee to prepare reports proposing options with their costs and consequences for the public health authority. When a decision is made, the implementation of the new program is carefully planned. Surveys and consultations with stakeholders are systematically conducted to identify potential obstacles. A fraction of the budget is always reserved for program evaluation and monitoring. At the present time, the recommended immunization schedule targets 15 different diseases and only 20 injections are offered up to 15 years of age. Vaccine uptake rate is high and, although a reduced number of doses are recommended for several vaccines, program effectiveness is highly satisfactory, as shown for hepatitis B, meningococcal and pneumococcal diseases.