Planning for the integration of human services can be supported by analysis of data from the administrative records of agencies that provide services. The power of these data becomes available to researchers and policy planners when the individual records of services delivered to children and families are integrated longitudinally and across service programs and settings. In this chapter, the authors illustrate the potential of integrated administrative data to inform human services reform by drawing on the experiences of Illinois state government in using administrative data to support planning for agency consolidation and for a new service delivery system. The authors focus in particular on how administrative data can inform agency-capacity and case-management planning. They also discuss how integrated administrative data can be used to support efforts by communities to join forces with the state to design and implement effective programs. In M. Little and D. Gordon (eds.) Exploring Research Methods in Social Policy Research. Ashgate Publishing Company, Aldershot, UK.