OBJECTIVE To assess parental attitudes and knowledge about children's vaccination. METHODS In this study, 20 day-care centers, 25 schools, and 6 health centers were randomly selected in Vilnius, and an anonymous survey of 2743 parents was conducted. Females made up 85.2% of all respondents, males--14.8%; the mean age was 35.7 years. RESULTS Two-thirds of respondents (66.7%) agreed that vaccines for children's immunization are safe; 80.7% stated that vaccination is more beneficial than harmful. Only 16.9% of parents indicated that vaccines cause adverse events more frequently than other medical treatment, 62.7% that vaccines are amongst the most effective and least costly forms of medical treatment, and 35.9% that vaccines always warrant protection. Majority of parents agreed that children's vaccination is essential (89.0%), and children should be vaccinated regularly according schedule (88.6%). Only 30.1% of respondents agreed with the idea of taking a newly developed vaccine even if it has been carefully tested for safety; 42.3% of respondents could afford to pay for nonreimbursed vaccines. On an average, 38.0% of respondents know that they should be revaccinated every 10 years against diphtheria and tetanus, 61.3% have never been vaccinated against influenza. The main sources of information on vaccination are medical institutions (92.2%), print media (38.1%), and broadcast media (38.2%). CONCLUSIONS While most of respondents can be characterized as having a positive opinion about vaccination, 20-40% of respondents indicated insufficient knowledge on this issue. For implementing the new vaccines, communication efforts should focus on clarifying correct parental beliefs about immunization. Vaccines for child should be reimbursed on the same basis as other medical treatment. Vaccination of adult and risk groups should be emphasized in the national vaccination program.