Analysis of NIBRS data on crimes against juveniles (ages 0 to 17) shows that babysitters are responsible for a relatively small portion of the reported criminal offenses against children: 4.2 percent of all offenses for children under age 6. This is far less than the percentage accounted for by family members. Among the reported offenses that babysitters commit, sex crimes outnumber physical assaults nearly two to one. Children most at risk of physical assaults by babysitters are younger (ages 1-3) than those at risk of sex crimes (ages 3-5). Males constitute the majority of sex-offending babysitters reported to the police (77 percent); females compose the majority of those who commit physical assaults (64 percent). Juvenile offenders are responsible for nearly half the babysitter sex crimes known to police (48 percent) but only 15 percent of the physical assaults. Babysitter offenses rarely result in death, but victims of babysitter crimes known to police are more likely than other child crime victims to suffer an injury (75 percent compared with 53 percent for victims under age 6). The incidence of babysitter crimes against children is large enough to justify precautions by parents in screening and hiring care providers. For an example of these precautions, see the suggested guidelines on "Choosing a Sitter" at the Prevent Child Abuse America Web site (www.preventchildabuse.org). 6 figures and 15 references