OBJECTIVE: The objectives of this research were to (1) obtain estimates of child maltreatment and other forms of personal, witnessing of, and indirect victimization among children aged 0 to 1 year in the United States and (2) examine associations between infant victimization exposure and the infant's level of emotional and behavioral symptoms. METHODS: The study is based on a cross-sectional national telephone survey that included caregivers of a sample of 503 children under 2 years of age. RESULTS: Nearly one-third of the sample of infants (31.6%) had experienced some form of personal, witnessing, or indirect form of victimization. The rate of infant maltreatment by caregivers (2.1%) was significantly lower than among older preschool-aged children. However, the rate of infant assault by siblings was considerable at 15.4%. The greatest risk of assault occurred in households with young siblings; nearly 35% of the infants with a sibling aged 2 to 3 years were assaulted in the year before the interview. Witnessing family violence was also relatively common among the infants (9.5%). Victimization was associated with emotional and behavioral problems; sibling assault and witnessing family violence had the highest correlations with infant symptom scores. CONCLUSION: The results of this study highlight the need for attention to infant victimization that considers a wider array of victimization sources and a broader scope of prevention efforts than has been typical in the child-maltreatment field.