The long term effects of multiphasic health screening (MHS) are rarely studied. In 1964 a random sample of 546 women and 544 men born 1899, 1904, 1909, 1914 or 1919 equally distributed on cohorts from the Swedish town Eskilstuna were invited to examination. For several reasons 167 persons (15%) did not participate in the study. In 1969 the whole sample was invited to a second MHS together with a control group that had not been exposed to MHS. Furthermore, 79 of those alive 1989 born 1899 or 1904 and examined 1964 and 1969 were reexamined. Over all survival rate 1989 for those examined 1964 was for males 18% and for females 35%. Screening instruments 1964 and 1969 were questionnaires, laboratory tests, antropometric measurements, ECG, measurement of blood pressure, chest radiography, peak expiratory flow (PEF), tonometry and fundoscopy of the eyes, audiometric screening, dental, gynecological and general clinical examination. Systolic hypertension for both sexes, low PEF and smoking, low cholesterol in women were negatively related to survival. Of 18 diabetics only one was alive at follow-up. No association was found between BMI and mortality for men, but some (1964 p < 0.01; 1969 p < 0.05) for women. Altogether 87 individuals were 1969 judged to have had some benefit of the MHS in 1964, 40 of them substantial. This was, however, not statistically significantly associated with improved survival. Of the reexamined survivors 86% reported to be generally satisfied with their life situation. The prognostic value of graded benefit was analysed in some detail. The survival to age 85 in the group allotted any benefit was somewhat less good (37%) than in the group with no benefit (44%). The difference did not reach statistical significance.