The purpose of the present study was to investigate the validity of the Working Group's Autobiographical Memory Test as a dementia screening tool for individuals with moderate to severe intellectual disabilities (ID). Twenty-one participants with Dementia of Alzheimer's Type (DAT) and moderate to severe ID and 42 controls with similar levels of ID were tested. The majority were re-tested one year after the initial evaluation. The DAT group scored considerably lower than the control group on the initial evaluation. The controls with DS exhibited a considerable decline on the follow-up evaluation whereas other participants exhibited little changes. This demonstrates an insignificant overall difference between the DAT group and the control group on the follow-up evaluation. Virtually all participants exhibited the same scores on 3 out of 6 test items and the percentage of participants who correctly answered the remaining three test items were not significantly different from the DAT or control groups. In conclusion, the Working Group's Autobiographical Memory Test may be useful as a dementia screening tool for individuals with moderate to severe ID from DS when validated with a large sample size study. However, it is questionable whether this test is a reliable dementia screening tool for individuals with moderate to severe ID from non-DS etiologies. This test has a significant psychometric weakness because of the restricted score variability among the participants. (Contains 2 tables.)