The model laws developed for child abuse reporting mandated that physicians report cases of suspected child maltreatment. Provisions in these laws would free them of any civil or criminal liability for such reporting. Within a 5-year span, every State had passed a child abuse reporting law, which required specified professionals likely to come in contact with children in the course of their work to report suspected maltreatment to child protective agencies. Over time there has been a substantial increase in the number of professional groups designated in State laws as mandated reporters. The reporting laws clearly have succeeded in encouraging the identification of abuse and neglect, as evidenced by the significant increase in the reporting rate. Since 1984, professionals have accounted for the majority of reports of child maltreatment. School personnel have been responsible for the largest number of reports. The success of the reporting laws, however, created substantial and unanticipated problems for the child protective agencies designated to receive the reports. Most lacked the capacity to respond adequately to a large share of the cases that were reported. Further, although the number of suspected cases reported to protective agencies increased significantly, not all of even the most serious cases of child maltreatment were being reported. A study identified three clusters of reasons for failure to report a suspected case of child maltreatment: the costs to the reporter of reporting the case, the professional's belief that he/she was more competent to deal with the case than the child protection agency, and belief that the evidence was not sufficient to make a report. Other sections of this chapter discuss victim and offender disclosure of maltreatment, the prevalence of physical abuse, the prevalence of sexual abuse, the relationship of victim and offender reports to official reports, when to report, and case management and disposition after reporting. Other issues addressed are the classification of cases after investigation, the substantiation decision, substantiation rates, reasons for failure to substantiate, proposals to improve child protective services operations, and system restructuring. 4 notes and 113 references