© 2014, The American Geriatrics Society. Objectives To validate the Mini-Mental State Examination (MMSE) Telephone (MMSET) against the MMSE.Design Cross-sectional.Setting Homes of community-dwelling older adults.Participants African-American and non-Hispanic white adults aged 75 and older participating in the University of Alabama at Birmingham Study of Aging II, a longitudinal epidemiological study across the state of Alabama (N = 419).Measurements Cognition, measured using the MMSE, MMSET, and Six-Item Screener (SIS), and function, based on self-reported difficulty performing instrumental activities of daily living (IADLs). Correlation and agreement coefficients were used to examine concordance of the MMSE and MMSET; linear and logistic regressions were used to test associations with clinical outcomes of IADL difficulty and verified diagnoses of dementia. Results The MMSET showed good internal consistency (Cronbach α = 0.845), similar to the full MMSE, and strong correlation with the latter (Spearman ρ = 0.694, P <.001). The MMSET explained a similar proportion of IADL difficulty as the full MMSE (coefficient of variation = 0.201 and 0.189, respectively). The MMSET was also associated with verified dementia diagnoses (area under the receiver operating characteristic curve = 0.73), which was similar to the full MMSE.Conclusion The MMSET is a brief, valid measure of cognition in older adults with psychometric properties similar to that of the full MMSE. Because it can be administered over the telephone, further use in epidemiological studies is promising.