The retirement income security of older Americans and the cost of providing that security are increasingly the subject of major debate. This volume assesses what we know and recommends what we need to know to estimate the short- and long-term effects of policy alternatives. It details gaps in data and research and evaluates possible models to estimate the impact of policy changes that could affect retirement income from Social Security, pensions, personal savings, and other sources. Table of ContentsFront MatterExecutive Summary1 Introduction2 Considerations in Retirement Income Predictions3 Key Research Issues4 Data Needs5 Development of Projection Models6 Furthering Coordination for Data Collection, Research, and ModelingAppendix A: Contents, Assessing Knowledge of Retirement BehaviorAppendix B: Retirement-Income-Related Data SetsAppendix C: Examples of Retirement-Income-Related Projection ModelsAppendix D: Major Aspects of DYNASIM2 and PRISMReferencesBiographical Sketches of Panel Members and StaffIndex