This Congressional Budget Office (CBO) study-prepared at the request of the Chairman and former Ranking Member of the Senate Committee on Finance-documents changes in the distribution of household income between 1979 and 2007. CBO's analysis examines the distribution of household income before and after government transfers and federal taxes, and it reports the contribution of various income components (such as wages and salaries, capital income, and business income) to the distribution of market income. The study presents information on trends in the distribution of income for all households combined and for households separated on the basis of age and the presence of children. In keeping with CBO's mandate to provide objective, impartial analysis, this study makes no recommendations.