The term recidivism is used to mean return to the child welfare system. Substantiation data are commonly used as a yardstick in policy debates, which increases the need for a sound understanding of the nature of substantiation and degree of difference or similarity between substantiated and unsubstantiated cases. This study addresses the question of whether substantiated victims and families return to child protective services at similar or different rates than do unsubstantiated victims and families. The question is examined both in a dataset representing victims and in a separate dataset constructed at the family or case level. The question is examined separately for sexual abuse, physical abuse, and neglect. The sample included child abuse and neglect reports from the Missouri Division of Family Services in 1993 or 1994. Bivariate analyses were presented along with survival tables and Cox proportional hazards models. These techniques allow prediction of outcomes while controlling for the time children or families are at risk of that outcome. The results of the study show that nearly half of the children and more than half of the cases returned to the attention of child welfare agencies within 4.5 years. Although dependent on type of maltreatment, level of recidivism, and service use, it was found that in general, unsubstantiated victims and cases experienced recidivism at a rate only slightly lower than did substantiated victims and cases. Although unsubstantiated events had a slightly lower rate of recidivism, they comprised a far higher volume of the re-reported events. The high levels of recidivism among unsubstantiated cases showed unambiguously that such cases were at high risk for subsequent maltreatment and showed clearly that these cases were not simply erroneous reports made against families unlikely to engage in child maltreatment. Unsubstantiated events are a significant concern due to the future risk for children and because of the sheer volume of unsubstantiated events. 2 figures, 4 tables, 40 references