172 persons with mild to moderate hypercalcaemia were followed up for 14 years. Life-table analyses showed that, among persons aged 70 years or less at the time of detection of the hypercalcaemia, survival was lower in the hypercalcaemic group than in a normocalcaemic age and sex matched control group. No such difference was found among older persons. The lower survival was related to degree of hypercalcaemia, and this held true when systolic and diastolic blood pressure, serum glucose, serum uric acid, and serum cholesterol were taken into account in a multivariate analysis. The lower survival seemed to be due mainly to deaths from diseases of the circulatory organs. No person with normal renal function at the beginning of the study period had a more than marginally raised serum creatinine at follow-up.