The elderly and disabled make up 24 percent of Medicaid enrollees, yet account for 70 percent of the programs's $275 billion in expenditures. Identifying health care programs that cut costs and maximize quality, therefore, is an ongoing challenge for states and other Medicaid stakeholders. A new online tool seeks to help states estimate the expected return on investment of proposed quality improvement initiatives. The ROI Forecasting Calculator is a front-end planning tool that prompts users to provide information about proposed initiatives including target-population characteristics, program costs and expected changes in health-care utilization. Since predicting utilization changes, such as a decrease in hospital admissions or an increase in pharmacy costs, might be challenging, users can reference the ROI Evidence Base. Available both in calculating the ROI and as a stand-alone resource, the ROI Evidence Base includes published studies on various clinical topics and data for initiatives by other states and health plans. The resulting forecasts can be used to predict the financial implications of an idea--or alternatively, users can start with a target ROI estimate and work backward. The calculator was developed by the nonprofit Center for Health Care Strategies and funded by the Robert Wood Johnson Foundation.