More observational studies and clinical trials have been conducted, more drugs have been approved for treatment, and more clinical practice guidelines have been written for hypertension than for nearly any other cardiovascular risk factor, yet hypertension still remains underrecognized and undertreated.1 Why does hypertension control remain so elusive in the United States? Current guidelines are intended to help clinicians diagnose hypertension and prescribe effective therapies for individual patients2 but offer little guidance to health systems on how to improve hypertension control in the populations they serve. This deficiency in the guidelines is largely attributable to the lack of science behind health system approaches to blood pressure control. Although substantial knowledge is available regarding the epidemiology, pharmacotherapy, and genetics of hypertension, many people with hypertension will remain underdiagnosed and undertreated if health systems cannot identify them more efficiently and eliminate barriers to delivering health care.