Data on 1888 patients seen at Alzheimer's Disease Diagnostic and Treatment Centers in California were used to examine possible differences in Mini-Mental State Examination (MMSE) results for different racial-ethnic groups. White patients had scores less indicative of dementia than Black and Hispanic patients using the standard 23 cutting point on the MMSE. However, there were no differences among these groups in the percentages clinically diagnosed as demented. The difference in the percentage of Whites vs Blacks and Hispanics categorized as demented by the MMSE was not accounted for by education, occupation, age, sex, or other variables tested, even though these variables were correlated with MMSE scores. Our data suggest that clinicians should consider MMSE scores for Black and Hispanic patients an underestimate of their cognitive capabilities relative to that of White patients.