Cross-sectional studies covered 2562 males (a urban population), 580 miners, 1126 agricultural drivers, 682 rural habitants and 4323 urban drivers. The mean blood pressures were basically identical in males of various occupations and age, except for urban and rural drivers aged 20-29 and 40-49 years who had significantly lower mean systolic blood pressures than those from the other groups under study. All the males showed elevation in systolic and diastolic blood pressures with age; the differences in blood pressures were insignificant only in rural drivers aged 30-39 and 40-49 years and miners aged 40-49 and 50-59 years. The incidence of arterial hypertension increased with age: from 3.2 to 7.7% in 20-29-year-old males to 34.2-37.2% in 50-59-year olds. Low (less that 50%) awareness of hypertension was identified in hypertensives. A prospective 5-year follow-up and implementation of prophylactic measures at the urban motor enterprises positively affected the incidence of hypertension and the level of hypertension awareness, and morbidity rates.