During October 2005-September 2006 (federal fiscal year 2006), approximately 905,000 U.S. children were victims of maltreatment that was substantiated by state and local child protective services (CPS) agencies. Approximately 19% of child maltreatment fatalities occurred among infants (i.e., persons aged <1 year), and homicide statistics suggest that fatality risk might be greatest in the first week of life. However, the risk for nonfatal maltreatment among infants has not been examined previously at the national level. To determine the extent of nonfatal infant maltreatment in the United States, CDC and the federal Administration for Children and Families (ACF) analyzed data collected in fiscal year 2006 (the most recent data available) from the National Child Abuse and Neglect Data System (NCANDS). This report summarizes the results of that analysis, which indicated that, in fiscal year 2006, a total of 91,278 infants aged <1 year (rate: 23.2 per 1,000 population) experienced nonfatal maltreatment, including 29,881 (32.7%) who were aged < or =1 week. Neglect was the maltreatment category cited for 68.5% of infants aged < or =1 week, but NCANDS data did not permit further characterization of the nature of this neglect. Developing effective measures to prevent maltreatment of infants aged < or =1 week will require more detailed characterization of neglect in this age group.