A family is described in which one member presented with symptoms and signs suggestive of corticobasal degeneration and a sibling presented with features of a frontal lobe dementia. Their mother developed a presenile dementia and movement disorder. At postmortem examination the member with clinical corticobasal degeneration had non-specific pathological features. Therefore, the clinical features of corticobasal degeneration can occur with non-specific pathological changes. Within a pedigree, different members can present with different clinical syndromes, which may reflect variation in the distribution and severity of the pathological process.