Distributional issues often lie at the center of tax policy debates. Distributional analysis may address several issues: How should the tax burden be distributed or, are progressive (increasing as a share of income as income rises) taxes justified? What is the estimated distribution of the current system? How does a particular proposal change that distribution? Unlike many analyses that study optimal behavior related to allocative issues and economic efficiency, economic analysis cannot be used to answer the questions of how the tax burden should be distributed. Such an answer would depend on social preferences. Economic analysis can, however, identify trade-offs and frame the issue analytically. For example, a number of plausible answers to this question could justify progressive tax structures. Methodological issues, such as the income classifier, the unit of analysis, and assumptions regarding incidence all affect the estimates of the distribution of the current tax burden. Yet all show a similar qualitative result: the federal tax system is progressive throughout its range, although it tends to get much flatter at the top. This pattern is primarily due to the individual income tax, which is quite progressive, and actually provides subsidies at lower income levels. The other major tax is ...