Depression is among the most common psychiatric disorders in Alzheimer’s disease (AD). Nevertheless, given the overlap between the symptoms of depression and the symptoms of dementia, diagnosing depression is still problematic. Several depression rating scales have been validated for use in AD. Both the Hamilton Depression Rating Scale and the Montgomery-Asberg Depression Rating Scale have been used for screening purposes, to measure the severity of depression, and for assessing response to treatment. The recommendation to diagnose depression in AD is by using structured psychiatric interviews, such as the Structured Clinical Diagnostic Interview for DSMâIV or the Mini International Neuropsychiatric Interview. Based on information obtained from the structured interviews, depression is diagnosed using DSMâIV criteria. Consensus groups suggested specific changes to the diagnostic criteria to account for the overlap of symptoms between depression and dementia, and recent studies validated the DSMâIV criteria for major depression for use in AD.