Although informant reports of everyday functioning are often used in dementia assessments, the actual correspondence between such indirect reports of functioning and actual performance has not been examined. Orientation results on the Dementia Questionnaire for Mentally Retarded Persons were compared to those obtained in direct assessment of orientation of 138 adults with mental retardation. Fair to good agreement was found between informant report and direct assessment. However, for some orientation items, nonverbal IQ, cause of mental retardation, and age affected the level of agreement. Thus, both informant report and direct measures of orientation are necessary in dementia assessments, and further work is needed on informant scale validation.