Health status, access to and quality of care, and numerous social factors associated with health vary across racial groups [1,2]. Many applaud the collection and use of race data to identify and monitor progress in addressing health disparities [3][4][5][6]. The National Institutes of Health (NIH) requires and the Food and Drug Administration (FDA) recommends the collection of race data in clinical research [7,8]; the 2009 Health Information Technology for Economic and Clinical Health (HITECH) Act provided financial incentives for health systems to collect race information through the Medicare and Medicaid Electronic Health Record Incentive Program (i.e., "meaningful use" of electronic health records) [9,10]; and the 2010 Patient Protection and Affordable Care Act (ACA) mandated that the Department of Health and Human Services establish standards for race and ethnicity data collection [11]. Yet, in the face of increasing amounts of "race data," we have created few opportunities for discussing "what race measures." Some journals require authors to explain how race is conceptualized and collected in their studies, but the requirement is not standardized and rarely met [12][13][14]. Thus, race and racial data are frequently interpreted in conflicting ways. This article seeks to provide an overview of race as a foundation for an improved understanding of the relationship between race and health.