OBJECTIVES: Although hypertension is a major risk factor for cardiovascular disease, medication adherence to hypertensive medications is low. Previous research identifying factors influencing adherence have focused primarily on  broad, population-based approaches. Identifying specific barriers for an individual is more useful in designing meaningful interventions. Using customized telephonic outreach,  we examined the specific barriers influencing hypertensive patients’ non adherence in order to identify targeted interventions. METHODS: Sample represented members from a health plan in 2008 with ≥ 2 prescriptions for hypertensive medications. Non adherent members had a Medication Possession Ratio (MPR) of < 80% for at least one of their hypertensive drugs. Telephone script was based on the “target” drug with the lowest MPR. Study was implemented in fall 2008. RESULTS: Response rate was 28.2% (n=8692); 22.6% commercial and 49.8% Medicare respondents. Mean age was 63.4, 54.3% were female; mean MPR was 61% for the target drug. Majority of respondents (~60%) had adherence levels between 60-79%. However, only 58.2% of Medicare and 60.4% of commercial respondents reported “missing a dose of medication”. Primary reason was forgetfulness (61.8% Medicare; 60.8% commercial) followed by “being too busy (2.5% Medicare; 17.2% commercial and “other reasons” (21.9% Medicare; 8.1% commercial) which included travel, being hospitalized or sick, disruption of daily events and unable to get to the pharmacy. Prescription copay was a barrier for < 5% of respondents. Taking medications as part of a daily routine (46.4% Medicare; 52.2% commercial) helped improve adherence. Low non adherence (0-59%) was associated with higher cardiovascular related expenditures ($11,800) compared to moderate (60-79%) non adherence ($8467). CONCLUSIONS: Despite elaborate models explaining non adherence, forgetfulness was the primary reason for self reported non-adherence in this study. Events interfering with daily routine also had significant impact on non-adherence. Novel interventions should address medication taking competency and promote a medication routine.