A crucial factor in promoting a vigorous quality of life in the aging population is assessment and treatment of cognitive deficits. A very high percentage of delirium and at least 20% of dementia is eminently treatable. This study of patients over 65 years of age admitted to a university general hospital reveals that 79% of cognitive deficits were missed by the examining physicians. Furthermore, in 394 examinations of 165 patients, only four mental status examinations were recorded. A clear-cut cognitive deficit on admission was predictive of later acute episodes of confusion. The global techniques of evaluation deserve remediable action by medical schools and hospital training programs if the medical care of the elderly is to be improved.