Background A 66-year-old man presented with a 3-year history of personality changes marked by increasing apathy, social withdrawal and deficits in complex attention, and a 1-year history of progressive memory problems and difficulties in planning and carrying out complex tasks. Investigations Three neuropsychological examinations over 2 years, neurological examination, routine laboratory tests, brain MRI, single-photon emission CT scan, genetic analyses, and neuropathological examination. Diagnosis A clinical diagnosis of frontal-variant frontotemporal dementia was superseded by postmortem neuropathological evidence, which established a diagnosis of frontal-variant Alzheimer's disease. Management The patient and his spouse were referred for counseling, and the patient was referred for follow-up examinations.