Health care systems have a key role in improving hypertension control in large populations, a global challenge, through the implementation of modern multicomponent programs. The impact of such programs in at-risk minority populations, nonetheless, remains to be better characterized. Additionally, the extent to which hypertension control based on a single time-point blood pressure (BP) measurement (LAST-BP), the approach typically used in health system performance assessment, agrees with time-averaged BP (AVG-BP) has not been well studied. Leon Medical Centers (LMC), a major integrated health care system serving Medicare beneficiaries predominantly of Hispanic origin in Miami-Dade County, Florida, implemented a hypertension control program in 2011. We conducted longitudinal data analysis evaluating hypertension control before and after program implementation, and compared annual rates derived from AVG-BP versus LAST-BP. During 2008-2018, the analytic sample increased from 4,710 to 21,540, mean age rose from 73.4 to 77.1 years, and the proportion of Hispanics remained stable (>98%). Adjusted odds of hypertension control were 5.7 (95% CI: 5.4-6.0) times higher after full program implementation. Improvements were comparable in women and men. Trends based on LAST-BP paralleled those of AVG-BP, although rates were consistently lower. Kappa agreement between AVG-BP and LAST-BP metrics was only fair. The LMC program was associated with a meaningful, sustained increase in hypertension control to high levels (crude rates based on AVG-BP ∼ 90%). LAST-BP-based control rates underestimated those derived from AVG-BP. Research is warranted to determine how longitudinal BP metrics can be optimally incorporated into patient care and health system performance assessment. Practical Applications: This study has two practical implications. First, it shows that a coordinated, multicomponent hypertension control program with modern core elements, including team-based care, standardized blood pressure measurement, and promotion of guideline-based management supported by a robust EHR system and enhanced pharmacy and transportation services, and culturally tailored patient engagement, can achieve and sustain high levels of hypertension control in the understudied population of Hispanic Medicare beneficiaries in South Florida. These findings provide a strong foundation for real-world primary care settings, while highlighting the need for continued program refinement as the science of blood pressure (BP) control in large populations evolves. Second, the study shows that a single annual "snapshot" BP value underestimates true hypertension control compared with the average of readings obtained throughout the year. This finding supports the value of longitudinal BP metrics and highlights the need for research to determine how best to incorporate them into performance assessment.