The aim of this study was to determine the accuracy of the Mini-Mental Status Examination (MMSE) as a screening test for dementia in an elderly Swedish population. All the inhabitants over 74 years of age in one area of Stockholm took the MMSE. The test was then compared to the clinical diagnosis of dementia. With a cut-off point of 23/24, the MMSE had a sensitivity of 87%, specificity of 92%, and positive predictive value (PPV) of 69%. Age, sex, and education did not substantially affect the specificity and the PPV, but had a slight effect on the sensitivity. The main causes of the false positives were somatic and psychiatric disorders. These results are in agreement with studies performed with similar methods and comparable populations.