Of all the statistics gathered in government-sponsored surveys, perhaps none is more ubiquitous than income, or more universally germane to a wide array of important policy issues.  This paper reviews research evidence on the quality of survey measures of income, with a particular focus on survey programs of the U.S. government.  Its primary intent is to assess what is known about the magnitude and nature of the errors made by individual respondents in providing survey reports of income, as well as what is known about the cognitive bases of those errors.