Using Health and Retirement Study data linked to summary plan descriptions and W-2s, this study reports trends in retirement wealth inequality of older employees 1992–2010. The study identifies and corrects methodological flaws in past research. Retirement wealth is highly unequally distributed; the top lifetime earnings quintile holds half of all retirement wealth, the bottom quintile, only 1%. The top earnings quintile fared better in 2010 than in 1992, whereas bottom-quintile earners fared worse. But retirement wealth inequality mainly reflects inequality within earnings quintiles, resulting from inadequate savings, not outsize accumulations. Systemic flaws reduce median retirement wealth by 84%