The Federal Employee Retirement System (FERS) quses a three tiered approach to retirement income: The FERS comprises Social Security, a defined benefit pension, and an individual savings plan called the Thrift Savings Plan (TSP). A number of the plans to reform Social Security include providing individuals with the opportunity to save and invest on their own. This 29-page paper by Laurel Beedon of PPI examines the TSP from a number of perspectives to determine whether the TSP is a viable model for an individual investment tier for Social Security. The paper begins by describing what Congress intended when it created the TSP, how the plan's administrative design and investment options reflect that intent. It goes on to discuss how employees have responded to the plan and what it offers. The paper concludes that the TSP provides some valuable information on how an individual, tax-favored, voluntary savings/investment account works when added to a program that includes Social Security and a pension. If, however, it is to be used as a model for reform of Social Security it must be remembered that the TSP represents 2.3 million workers, whereas Social Security represents 129 million. Thus, using the TSP as a model requires some caution.