The review found that the CWS includes a subset of parents who are also in the substance abuse treatment system and vice versa. Although the overlap between the CWS and substance abuse treatment systems may be extensive, CWS is not required to become involved in substance abuse issues of clients unless substance abuse is determined to be a factor in child abuse or neglect. CWS is not organized to manage the recovery of parents in substance abuse treatment. In addition, courts that have jurisdiction in cases of child maltreatment are not required to report data on child welfare cases or on the subset of court cases in which parental substance use is a factor. Similarly, the substance abuse treatment system is not required to address the needs of children whose parents are in treatment. It will take a strong effort by policymakers and administrators to establish a mechanism for accessing the data from each system in order to facilitate the coordination of family services. The literature review focused on the content of data systems for child welfare and substance abuse treatment, research studies on the prevalence of substance use disorders in the child welfare population, child abuse and neglect among parents in substance abuse treatment, prenatal substance exposure, system overlaps and data gaps, and opportunities to close the gap. 2 tables and 36 references