This chapter talks about a 77-year-old right-handed woman who presented to clinic with a 7-year history of slowly progressive difficulty with visuospatial processing followed by language and memory dysfunction. The general physical examination was normal. On mental status examination, the patient was alert and fully oriented. Her speech was fluent with occasional word finding pauses. Based on the patient's history of slowly progressive visuospatial dysfunction followed by mild deficits in language and memory, physical and cognitive examination findings suggestive of biparietal dysfunction and marked parietal atrophy on brain imaging, the patient was diagnosed with posterior cortical atrophy (PCA). The most likely underlying histopathology was felt to be Alzheimer's disease (AD), based on the strong relationship between the PCA clinical syndrome and underlying AD. Corticobasal degeneration was also considered, but was felt to be less likely given the paucity of movement abnormalities and Parkinsonian features seven years after symptom onset.