A health promotion and screening program for the detection of the major risk factors for ischemic heart disease was carried out in 1990 among the employees (n = 4,521; 70% female) of the Centre Hospitalier Universitaire Vaudois (CHUV). The prevalence of risk factors among the 1,425 employees (73% female) who took part in the study (participation rate: males 29%, females 33%) was compared with the prevalence of risk factors within three other populations: 1) new CHUV employees, who are systematically screened (n = 424: 71% female); 2) a representative sample of the general population; and 3) a group of employees from 44 companies located in the same region. Smoking was the most common of the three main risk factors; its prevalence was lowest among CHUV employees and highest among employees of the 44 firms. The prevalence of hypercholesterolemia and high blood pressure was variable among the different populations. These variations could partly be due to differences in methodologies and measurement conditions, but could not totally be explained in this way.