 We propose to test an intervention to increase patients understanding of the causes, consequences, and the rationale for treatment, of their hypertension HTN, as a strategy for increasing blood pressure BP control. The focus is on the interaction between a behavioral intervention to reduce BP - home BP monitoring HBPM - and patient knowledge, which, we propose, moderates the effect of the HBPM intervention. We hypothesize that patients who have a better understanding of their illness and its prescribed treatment will be more adherent to the treatment regimen, and thus will exhibit improved outcomes compared to those who have been exposed to the same intervention, but who do not have a clear understanding of these elements. 