The purpose of this study was to show a relationship between maternal and household demographic characteristics and refusal of some or all vaccines recommended for children under 35 months of age according to the Centers for Disease Control and Prevention Recommended Childhood Immunization Schedule. More specifically, this study aimed to demonstrate a significant relationship between vaccine refusal and a high level of maternal education (some college or more), higher than the median household income ($35,001- $50,000), and non-Hispanic white ethnicity. Data from the 2002 National Immunization Survey (NIS) were used, which implemented household telephone surveys and healthcare provider questionnaires to collect demographic information and vaccination statuses on 19- to 35-month-old children in the United States. Pearson chi-square and logistic regression analysis were performed to test the relationships between child, mother, and household demographic variables and 3 vaccination status categories: fully vaccinated, undervaccinated, and selectively unvaccinated. Selectively unvaccinated children were more likely to be female, to be in the 30-35 month age category, to be of Hispanic or non-Hispanic black ethnicity, to have a mother 30 years of age or older, to have a mother who was either widowed, divorced or separated, to have a mother who had 12 years of education, to live in a household with an annual income of $20,001-$35,000, to live in a single-child household, and to live in a state that does not allow philosophical exemptions to school-entry immunization requirements. Whereas, undervaccinated children tended to be male, to be younger than 30 months, to be non- Hispanic white, to have a mother who was younger than 30 years and married, to have a mother who had 12 years of education or had graduated college, to live in a household whose income was not the median level, to live in a household with at least one other child, and to live in a state allowing philosophical exemptions to immunization requirements. Although other studies have shown that parents who refuse all vaccines for their children tend to be white, more highly educated, and live in higher-income communities, the results of this study suggest that there may not be clear-cut demographic characteristics that define parents who selectively refuse vaccines. Consequently, there may not be specific populations for health promotion campaigns and healthcare providers to target in an effort to increase vaccine uptake. While it is important for the good of the society that herd immunity is maintained in communities, it is essential that parents retain the autonomy to choose what they believe is best for their child's health. Thus, healthcare providers have a responsibility to ensure parents are educated on the risks and benefits of vaccination so they can make informed immunization decisions for their children.