Patient knowledge and awareness of hypertension are important factors in achieving blood pressure control. To examine hypertensive patients' knowledge of their condition, the authors randomly surveyed 2500 hypertension patients from a large health maintenance organization; questionnaires were supplemented with clinic blood pressure measurements. Approximately 72% of the subjects completed surveys. Of patients with uncontrolled hypertension (systolic blood pressure [SBP] > or =140 mm Hg and/or diastolic blood pressure [DBP] > or =90 mm Hg), only 20.2% labeled their blood pressure as "high" and 38.4% as "borderline high". Forty percent of respondents couldn't recall their most recent clinic-based SBP and DBP values. Overall, 71.7% and 61% were unable to report a target SBP or DBP, respectively, or identify elevated targets based on the sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI) criteria. Most patients perceived DBP to be a more important risk factor than SBP. Hypertensive patients awareness of blood pressure targets and current hypertension control status, particularly with respect to SBP, is suboptimal. The authors' findings support the need to improve patient education for better management of hypertension.