Data were obtained from a household survey, a juvenile facilities survey, a returned runaway study, a police records study, an FBI data reanalysis, and a community professionals study. The findings indicate that many of the children in at least four of the categories were not literally missing. Caretakers knew where they were, and the problem was in recovering them. Family abduction was apparently a larger problem than previously thought, and the runaway problem was not larger in 1988 than at the time of the last national survey in 1975. More than a fifth of the children who had previously been termed runaways should actually be considered "thrownaways." There was a large group of children missing because they were lost or injured or because they miscommunicated with caretakers about where they would be or when they would be home. Because of definitional controversies and confusion about the concept of missing children, the report recommends that public policymakers clarify the problem. 13 figures.