I have developed a three part, brief, cost effective protocol for differentially diagnosing the presence of the 3 D's in older adults exhibiting a progressive and sustained change in mental functioning and/or behavior. Elders, and/or their spouses, children or other family members typically contact me to advise them regarding such changes. Following an initial “family history” interview, the elder of concern is evaluated alone at my midtown office or in the comfort of their home. We conclude with a follow up family session where the findings are reviewed and a prognosis and action plan for eldercare services is discussed.