With cost of vaccines steadily increasing, recommendations of the Advisory Committee on Immunization Practices (ACIP) have growing economic implications for the public. We used semi-structured telephone interviews to assess the knowledge, attitudes, and practices of the 15 voting members of the 2006-2007 ACIP regarding the use of economic information by the committee in their deliberations about new vaccine recommendations. These interviews demonstrated the importance of economic information in ACIP deliberations, but also revealed that many members felt economic information should not be outweighed by the more important issues of vaccine efficacy, disease burden, and safety. In addition, though members had variable levels of expertise in analyzing economic data, there was a general concern that assumptions inherent in the development of cost-effectiveness models made interpretation of the data resulting from these models difficult. To counteract this concern, several ACIP members suggested standardizing the process of how economic data are presented to the committee so that a more uniform consideration of consequential information might be undertaken by the ACIP in their deliberations.