The uniformity of the neuropsychological deficits found in different forms of subcortical dementia has received limited attention. This is particularly true of relatively rare disorders such as Hallervorden-Spatz syndrome and Fahr's disease. The current investigation presents case study data related to the neuropsychological functioning of 12 patients with different forms of subcortical dementia. Findings are consistent with proposed subcortical characteristics of psychomotor slowing, impaired retrieval, and personality/mood alterations within a context of unimpaired vocabulary, verbal abstraction, and recognition memory. Heterogeneity is noted across cases on neuropsychological tasks of attention/concentration, naming, verbal fluency, visual constructional abilities, and visual memory. Contrasting clinical features may indicate dementia progression, individual variability, or anatomic subgroups.