The purpose of this roundtable is to explore the imperfect art of estimating the budget costs of health insurance proposals—called scoring when done by government agencies. The panel addresses the complexities involved in generating these estimates, which usually depend on many untested and untestable assumptions. For example, the Medicare prescription drug “donut hole” was invented so that policymakers could achieve budget targets. These budget scores play a critical role in the design of health policies, as well as in the reform proposals put forth by candidates in an election. The roundtable discusses how policymakers can and do use health policy estimates and budget scores.