The authors report results from medical screening for hypertension carried out on the entire adult population (aged greater than 20 years) of the county of Nord-Trøndelag, Norway. Previously undiagnosed hypertensives in need of medical treatment (n = 173), false positives (n = 233) and patients in need of continued blood pressure monitoring (n = 474) were followed up 10 to 36 months after the screening. This group was compared with a random population sample of known hypertensives (n = 206), patients previously treated for hypertension (n = 118) and normotensives (n = 2,326). No significant differences in changes in quality of life (subjective well-being) were observed between the two groups from screening to follow-up. However, negative events in life and chronic stresses other than the fact of becoming sick induced a deterioration of quality of life. Positive events induced an improvement in quality of life.