Children aged <2 years are at increased risk for influenza-related hospitalizations, and those aged <5 years have more influenza-related health-care visits than older children. In 2004, the Advisory Committee on Immunization Practices (ACIP) recommended annual influenza vaccination of children aged 6-23 months. Two doses, at least 4 weeks apart, were recommended to fully vaccinate children aged <9 years who were receiving influenza vaccination for the first time. To assess influenza vaccination coverage among children aged 6-23 months during the 2005-06 influenza season, data from the 2006 National Immunization Survey (NIS) were analyzed. This report describes the results of that analysis, which indicated that 31.9% of children in this age group received at least 1 dose of influenza vaccine and 20.6% were fully vaccinated according to ACIP recommendations; however, results varied substantially among states. The results underscore the need to continue to monitor influenza vaccination coverage among young children, develop systems to provide childhood influenza vaccination services more efficiently, and increase awareness among health-care providers and caregivers about the effectiveness of influenza vaccination among young children.