Medication prescribing practice changed following the publications of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) in 2002 and the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC 7) in 2003. Few data are available on changes in hypertension control rates for patients initiating antihypertensive treatment before and after these publications. The authors compared systolic and diastolic blood pressure (SBP and DBP) levels and hypertension control (SBP<140mmHg and DBP<90mmHg) rates in patients initiating antihypertensive treatment in a large managed care organization during 2 time periods: July 1, 2001, to June 30, 2002 (n=322); and July 1, 2003, to June 30, 2004 (n=323). The blood pressure reduction associated with antihypertensive medication initiation was similar in 2001-2002 and 2003-2004 (-11.9 and -10.5mmHg, respectively, P=.251 for SBP; -6.9 and -5.9mmHg, respectively, P=.160 for DBP). The mean SBP and DBP prior to treatment were significantly lower in 2003-2004 vs 2001-2002 (145.4 vs 151.3mmHg, P<.001 for SBP; 87.6 vs 90.1mmHg, P<.002 for DBP). Hypertension control rates increased from 38.0% to 50.2% (P=.005) from 2001-2002 to 2003-2004. Lower pretreatment SBP and DBP explained hypertension control improvement over time. In this real-world clinic population, antihypertensive treatment was initiated at lower blood pressure levels following publication of ALLHAT and JNC 7, resulting in substantial improvements in hypertension control rates. © 2012 Wiley Periodicals, Inc.