Casual blood pressures were recorded in 331 Lapps and 221 Skolts over the age of 20. The systolic pressure was found to rise more with age in women than in men. In neither sex did age affect the diastolic pressure. A general tendency towards higher blood pressure in Lapps than in Skolts was noted up to the age of 50-60 years. Comparison with a Finnish population and one from the Aland Islands revealed similar systolic blood pressures in females, but definitely lower values in male Lapps and Skolts. The Lapps and Skolts did not have the clear age dependence of the diastolic blood pressure as occurs in Finns. These findings, together with other population studies, support the hypothesis that the setting of the resting blood pressure level is influenced by different kinds of stress associated with technological development and with an urbanized way of life.