OBJECTIVES: Adherence to therapy is one of the basic preconditions of successful treatment of hypertension. Unfortunately, many patients take their medication incorrectly. The aim of this study was to assess doctors' knowledge of this phenomenon, including interventions able to improve patient adherence. METHODS: It was a questionnaire-based survey conducted among a primary care network in Ukraine. The prescriptions were clustered as compliant and non-compliant prescriptions. All obtained data were analyzed using descriptive and inferential statistics. RESULTS: One hundred and forty five primary care physicians took part in the study. According to participants, hypertensive patients took on average 68.7 ± 15.4% of doses of prescribed drugs. Over half of respondents claimed that during the first year of treatment, no more than 23% of hypertensive patients discontinue their therapy. Survey participants pointed at patients discourage (38.8%) and lack of knowledge about disease (21.1%) as the main reasons for discontinuation of therapy. Almost 2/3 of participants (64.5%) claimed that they could recognize non-adherence in their patients. Prescribing combination drugs (71.3%), drugs with one daily dosing (62.6%), and affordable ones (51.7%) were the most common interventions aimed at improving adherence provided by respondents. CONCLUSIONS: Survey participants were aware of the phenomenon of non-adherence in patients with hypertension, but underestimated the real prevalence and seriousness of it. They also overestimated their ability to recognise non-adherence in their patients. Therefore, not necessarily they may obtain better adherence in their hypertensive patients. These results point at the issues which should be addressed in pre- and postgraduate education of physicians treating chronic cardiovascular conditions.