A national survey of 10,367 households uncovered cases of missing children that did not fall into one of the four federally defined categories of missing children. Qualitative and quantitative procedures disclosed the existence of four additional categories: children missing due to injury in an accident, delinquent and rebellious behavior, getting lost, and miscommunication among adult caregivers. Two of these categories, injured and lost children, should particularly be included in missing children's typologies because of their potential seriousness. Vulnerability to all four kinds of episodes was associated with certain family characteristics, suggesting that they were not simply accidental occurrences. In addition to help in locating their children, these families may need other forms of assistance.