Arterial blood pressure has been measured using mercury sphygmomanometer and auscultatory method for more than a hundred years. The results obtained by this measurement method make the basis of almost all conclusions related to pathogenesis, epidemiology and treatment of arterial hypertension. However, some deviations from ordinarily obtained data have been observed but are undoubtedly due to superficial approach to this simple method. A number of lesser faults can together result in an eventually inaccurate conclusion both regarding diagnosis and assessment of therapeutic effects. The aim of this short review article is to remind us of those little efforts needed to be done for improving the exactness of measurement in order to increase the accuracy of results. The ultimate consequence should be better care of patients with high blood pressure.