From year to year, child welfare directors allocate resources in the hope that their efforts will improve children's outcomes. Recently, with the help of the federal government, states have invested significant resources in the sort of information technology needed to run a smarter, more accountable child welfare system. In addition, science has made real progress when it comes to measuring change in complex systems. In this paper, we present a framework that state and local child welfare agencies might use to monitor their return on investments in child welfare services. The focus is on outcomes within the traditional child welfare system, which covers child maltreatment and foster care. The goal is to burrow through the complexity that goes along with trying to understand whether system performance is improving and whether the improvements are connected to changes in how resources are invested. This framework starts with a statement about the outcomes that are central to the child welfare system. We go on to focus on the process and quality of care as they relate to agency management. Finally, we discuss measurement, with specific emphasis on core outcomes and the problem of detecting change over time. Appended is a figure that illustrates the many pathways children may take on their way to being served in a given calendar year. (Contains 8 tables, 3 figures and 40 footnotes.)