This policy brief from the Center for American Progress highlights the importance of collecting demographic data to measure and then drive improvements in reducing health care disparities. It highlights some of the issues to be considered by the U.S. Department of Health and Human Services (HHS) in implementing section 4302 of the Patient Protection and Affordable Care Act (PPACA), which requires standardization of the collection of race, ethnicity, primary language, sex, and disability status data to identify and reduce health disparities. The brief notes the roles that parts of HHS could play in improving racial, ethnic and language data collection and the other opportunities in the PPACA to improve the collection and utilization of demographic data.