Background Effectively reducing cardiovascular disease disparities requires identifying and reducing disparities in risk factors. Improved understanding of hypertension disparities is critical. Methods Cross-sectional analysis of nationally representative samples of black and white adults 20 years and older who participated in the National Health and Nutrition Examination Survey (NHANES) 1999-2002 (white, n = 4624; black, n = 1837) and NHANES III conducted in 1988-1994 (white, n = 7121; black, n = 4709). We examined differences in hypertension prevalence, awareness, treatment, and blood pressure (BP) control among both treated and prevalent cases across the 2 periods. Results Hypertension prevalence increased significantly from 35.8% to 41.4% among blacks and from 24.3% to 28.1% among whites and remains significantly higher among blacks. Awareness is higher among blacks (77.7% vs 70.4%; P<.001), as is treatment (68.2% vs 60.4%; P<.001). These results are driven by higher rates in black women. Blood pressure control rates among those treated have increased in both races, primarily as a result of increased BP control in black and white men (27.3% and 44.7%, respectively; P.03). Despite the improved BP control rates, disparity in BP control among treated cases increased, with 59.7% of treated whites and 48.9% of treated blacks now reaching BP goal (P<.001). Racial differences in BP control rates among those treated cannot be explained by nonpharmacologic management or health insurance, but educational attainment is associated with BP control. Conclusion The higher prevalence of hypertension in blacks and the growing disparity in BP control among those treated pharmacologically are causes for concern.http://archinte.ama-assn.org/cgi/content/full/165/18/2098