AIMS To report levels of cardiovascular risk factors in 1985, 1990 and 1995 in three population samples in Göteborg, Sweden, and to compare with previous population risk factor levels. POPULATION The study was performed within the framework of the WHO MONICA Project which compares risk factor levels as well as the incidence of coronary heart disease and stroke in 38 populations. METHODS Three random samples of men and women aged 25-34, 35-44, 45-54 and 55-64 comprising 152-218 subjects in each age group who responded to the invitation for screening procedures which included questionnaires, physical and laboratory investigations in 1985, 1990 and 1995. RESULTS More men than women had smoked, except for those aged 35-44 where there was no difference between men and women. The proportion of men who had smoked decreased strongly between the first and third investigations (P < 0.0001), particularly amongst the younger age-groups, with a similar tendency amongst women. In the 25-44-years age group there was a tendency towards more women than men to be smokers in 1995. Snuff was used by 27% and 19% of men aged 25-34 and 35-44 years, respectively, in 1995. Up to 5% of women used snuff; higher in the younger age groups. More young men than women reported regular physical activity during leisure time with a tendency towards an increase from 1985 to 1995. The proportion of men reporting psychological stress varied little over the study period, but women aged 25-34 reported increased stress from 1985 to 1995. Body weight increased whereas height remained stable and consequently body mass index increased in men and women (P = 0.0001). Similarly, waist:hip ratio (measured in 1990 and 1995 only) also increased (P = 0.0001). Mean systolic and diastolic blood pressure increased with age and there was also a small increase between 1985 and 1995. Systolic blood pressure increased by a mean of 1.24 mmHg per 5-year period independent of sex and age (P = 0.0001). Antihypertensive treatment increased with age, but was stable between 1985 and 1995. Serum total and LDL cholesterol concentrations increased with age, and there was a nonsignificant tendency also to higher HDL cholesterol concentrations at older ages. Serum total cholesterol concentration declined between 1985 and 1995, and HDL cholesterol declined significantly between 1985 and 1995 in all age groups for men and women only when all age groups were analysed together. Similar to total cholesterol, levels of LDL cholesterol declined between 1985 and 1995 for all ages. Serum triglyceride levels increased for men and women between 1985 and 1995.