With people having the luxury of living longer there is an increasing epidemic of dementia throughout the world. It is important to distinguish true dementia from the not-unexpected loss of mental acuity as people age. This latter process has been termed “benign forgetfulness of senescence.” We are all probably susceptible to memory loss if we live long enough. Progressive cognitive impairment to a clinically significant degree, with no obvious identifiable factor, such as a metabolic disturbance, drug intoxication, or medication effect, probably indicates a dementing illness, however.