Despite the fact that invasive Streptococcus pneumoniae remains a leading cause of death, current levels of immunization in the at risk population remain low and well below the 90% goal for Healthy People 2010. A number of intervention strategies to increase immunization rates (for influenza and pneumonia) have been demonstrated to be effective in increasing these rates when used alone or in combination. A summary of this literature is presented including recent data on the effectiveness of pay-for-performance approaches for increasing preventive care. Data are also presented on intervention strategies judged to be most effective in a large health care system, the Veterans Health Administration, which has essentially reached the Healthy People 2010 goal for pneumococcal immunization.