This booklet provides guidance to law enforcement officers investigating missing children cases, whether through parental kidnappings, abductions by strangers, runaway or "throwaway" cases, and those in which the circumstances are unknown. The guide describes, step-by-step, the investigative process required for each of the four types of missing child cases. The guide also includes instructions on how to put information about missing children into the National Crime Information Center's computerized system. In addition, the booklet offers suggestions for forming police-social worker teams to work on missing and exploited children cases. The introduction defines types of missing child investigations and phases of case investigations. The National Center for Missing and Exploited Children is described. The booklet is divided into sections on initial response, voluntary missing cases, parental kidnapping cases, nonfamily abductions, National Crime Information Center (NCIC), and police/social worker teams. The appendix includes a missing child poster format, NCIC Missing Person Report Form, NCIC Unidentified Person Report Form, Exploited/Missing Child Task Force Form, Federal Parent Locator Service Authorization Form, and a list of state clearinghouses. (ABL)