 The analysis provides national estimates of the limited English proficient, LEP, population enrolled in Medicare, Medicaid, or both programs, DUALS, which were derived from the 2014 American Community Survey Public Use Micro-Data Sample, ACSP-UMS. The LEPMM was concentrated along the western and eastern coastlines and the southwestern region, with California and New York each containing more than 1 million lapms. The LEPMM was also highly diverse with varying disability status, and most were racial or ethnic minorities and elderly. These findings provide a foundation for measuring an understudied and at-risk population that will enable population health professionals to develop effective culturally and linguistically appropriate services and policies that address health disparities in the LEPMM. This article was authored by Kimberly Proctor, Shondell M. Wilson-Fredrick, and Samuel C. Haffer.